Basic upload functionality to predifined location, with basic file browser

author: Joe Robinson <joe@lc8n.com> 2010-10-27 14:21:09 +0100
committer: Joe Robinson <joe@lc8n.com> 2010-10-27 14:21:09 +0100
commit: 063284837c8c366e5502b1b0264b8eb807b61732 (patch)
tree: fff3a1e1e5afaa671485b9d990704658276627ac /org/apache/commons/net/nntp
12 files changed, 4064 insertions, 0 deletions
diff --git a/org/apache/commons/net/nntp/Article.java b/org/apache/commons/net/nntp/Article.java
new file mode 100644
index 0000000..cccba3b
--- /dev/null
+++ b/org/apache/commons/net/nntp/Article.java
@@ -0,0 +1,253 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+import java.util.ArrayList;
+import java.util.StringTokenizer;
+
+/**
+ * This is a class that contains the basic state needed for message retrieval and threading.
+ * With thanks to Jamie  Zawinski <jwz@jwz.org>
+ * @author rwinston <rwinston@apache.org>
+ *
+ */
+public class Article implements Threadable {
+    private int articleNumber;
+    private String subject;
+    private String date;
+    private String articleId;
+    private String simplifiedSubject;
+    private String from;
+    private StringBuffer header;
+    private StringBuffer references;
+    private boolean isReply = false;
+    
+    public Article kid, next;
+
+    public Article() {
+        header = new StringBuffer();
+    }
+
+    /**
+     * Adds an arbitrary header key and value to this message's header.
+     * @param name the header name
+     * @param val the header value
+     */
+    public void addHeaderField(String name, String val) {
+        header.append(name);
+        header.append(": ");
+        header.append(val);
+        header.append('\n');
+    }
+    
+    /**
+     * Adds a message-id to the list of messages that this message references (i.e. replies to)
+     * @param msgId
+     */
+    public void addReference(String msgId) {
+        if (references == null) {
+            references = new StringBuffer();
+            references.append("References: ");
+        }
+        references.append(msgId);
+        references.append("\t");
+    }
+
+    /**
+     * Returns the MessageId references as an array of Strings
+     * @return an array of message-ids
+     */
+    public String[] getReferences() {
+        if (references == null)
+            return new String[0];
+        ArrayList<String> list = new ArrayList<String>();
+        int terminator = references.toString().indexOf(':');
+        StringTokenizer st =
+            new StringTokenizer(references.substring(terminator), "\t");
+        while (st.hasMoreTokens()) {
+            list.add(st.nextToken());
+        }
+        return list.toArray(new String[list.size()]);
+    }
+    
+    /**
+     * Attempts to parse the subject line for some typical reply signatures, and strip them out
+     *
+     */
+    private void simplifySubject() {
+            int start = 0;
+            String subject = getSubject();
+            int len = subject.length();
+
+            boolean done = false;
+
+            while (!done) {
+                done = true;
+
+                // skip whitespace
+                // "Re: " breaks this
+                while (start < len && subject.charAt(start) == ' ') {
+                    start++;
+                }
+
+                if (start < (len - 2)
+                    && (subject.charAt(start) == 'r' || subject.charAt(start) == 'R')
+                    && (subject.charAt(start + 1) == 'e' || subject.charAt(start + 1) == 'E')) {
+
+                    if (subject.charAt(start + 2) == ':') {
+                        start += 3; // Skip "Re:"
+                        isReply = true;
+                        done = false;
+                    } else if (
+                        start < (len - 2) 
+                        && 
+                        (subject.charAt(start + 2) == '[' || subject.charAt(start + 2) == '(')) {
+                        
+                        int i = start + 3;
+
+                        while (i < len && subject.charAt(i) >= '0' && subject.charAt(i) <= '9')
+                            i++;
+
+                        if (i < (len - 1)
+                            && (subject.charAt(i) == ']' || subject.charAt(i) == ')')
+                            && subject.charAt(i + 1) == ':') {
+                            start = i + 2;
+                            isReply = true;
+                            done = false;
+                        }
+                    }
+                }
+
+                if (simplifiedSubject == "(no subject)")
+                    simplifiedSubject = "";
+
+                int end = len;
+
+                while (end > start && subject.charAt(end - 1) < ' ')
+                    end--;
+
+                if (start == 0 && end == len)
+                    simplifiedSubject = subject;
+                else
+                    simplifiedSubject = subject.substring(start, end);
+            }
+        }
+        
+    /**
+     * Recursive method that traverses a pre-threaded graph (or tree) 
+     * of connected Article objects and prints them out.  
+     * @param article the root of the article 'tree'
+     * @param depth the current tree depth
+     */
+    public static void printThread(Article article, int depth) {
+            for (int i = 0; i < depth; ++i)
+                System.out.print("==>");
+            System.out.println(article.getSubject() + "\t" + article.getFrom());
+            if (article.kid != null)
+                printThread(article.kid, depth + 1);
+            if (article.next != null)
+                printThread(article.next, depth);
+    }
+
+    public String getArticleId() {
+        return articleId;
+    }
+
+    public int getArticleNumber() {
+        return articleNumber;
+    }
+
+    public String getDate() {
+        return date;
+    }
+
+    public String getFrom() {
+        return from;
+    }
+
+    public String getSubject() {
+        return subject;
+    }
+
+    public void setArticleId(String string) {
+        articleId = string;
+    }
+
+    public void setArticleNumber(int i) {
+        articleNumber = i;
+    }
+
+    public void setDate(String string) {
+        date = string;
+    }
+
+    public void setFrom(String string) {
+        from = string;
+    }
+
+    public void setSubject(String string) {
+        subject = string;
+    }
+
+    
+    public boolean isDummy() {
+        return (getSubject() == null);
+    }
+
+    public String messageThreadId() {
+        return articleId;
+    }
+    
+    public String[] messageThreadReferences() {
+        return getReferences();
+    }
+    
+    public String simplifiedSubject() {
+        if(simplifiedSubject == null)
+            simplifySubject();
+        return simplifiedSubject;
+    }
+
+    
+    public boolean subjectIsReply() {
+        if(simplifiedSubject == null)
+            simplifySubject();
+        return isReply;
+    }
+
+    
+    public void setChild(Threadable child) {
+        this.kid = (Article) child;
+        flushSubjectCache();
+    }
+
+    private void flushSubjectCache() {
+        simplifiedSubject = null;
+    }
+
+    
+    public void setNext(Threadable next) {
+        this.next = (Article)next;
+        flushSubjectCache();
+    }
+
+    
+    public Threadable makeDummy() {
+        return new Article();
+    }
+}
diff --git a/org/apache/commons/net/nntp/ArticlePointer.java b/org/apache/commons/net/nntp/ArticlePointer.java
new file mode 100644
index 0000000..a810cad
--- /dev/null
+++ b/org/apache/commons/net/nntp/ArticlePointer.java
@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+/**
+ * This class is a structure used to return article number and unique
+ * id information extracted from an NNTP server reply.  You will normally
+ * want this information when issuing a STAT command, implemented by
+ * {@link NNTPClient#selectArticle selectArticle}.
+ * @author Daniel F. Savarese
+ * @see NNTPClient
+ */
+public final class ArticlePointer
+{
+    /** The number of the referenced article. */
+    public int articleNumber;
+    /**
+     * The unique id of the referenced article, including the enclosing
+     * &lt and &gt symbols which are technically not part of the
+     * identifier, but are required by all NNTP commands taking an
+     * article id as an argument.
+     */
+    public String articleId;
+}
diff --git a/org/apache/commons/net/nntp/NNTP.java b/org/apache/commons/net/nntp/NNTP.java
new file mode 100644
index 0000000..225e064
--- /dev/null
+++ b/org/apache/commons/net/nntp/NNTP.java
@@ -0,0 +1,1022 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+
+import org.apache.commons.net.MalformedServerReplyException;
+import org.apache.commons.net.ProtocolCommandListener;
+import org.apache.commons.net.ProtocolCommandSupport;
+import org.apache.commons.net.SocketClient;
+
+/***
+ * The NNTP class is not meant to be used by itself and is provided
+ * only so that you may easily implement your own NNTP client if
+ * you so desire.  If you have no need to perform your own implementation,
+ * you should use {@link org.apache.commons.net.nntp.NNTPClient}.
+ * The NNTP class is made public to provide access to various NNTP constants
+ * and to make it easier for adventurous programmers (or those with special
+ * needs) to interact with the NNTP protocol and implement their own clients.
+ * A set of methods with names corresponding to the NNTP command names are
+ * provided to facilitate this interaction.
+ * <p>
+ * You should keep in mind that the NNTP server may choose to prematurely
+ * close a connection if the client has been idle for longer than a
+ * given time period or if the server is being shutdown by the operator or
+ * some other reason.  The NNTP class will detect a
+ * premature NNTP server connection closing when it receives a
+ * {@link org.apache.commons.net.nntp.NNTPReply#SERVICE_DISCONTINUED NNTPReply.SERVICE_DISCONTINUED }
+ *  response to a command.
+ * When that occurs, the NNTP class method encountering that reply will throw
+ * an {@link org.apache.commons.net.nntp.NNTPConnectionClosedException}
+ * .
+ * <code>NNTPConectionClosedException</code>
+ * is a subclass of <code> IOException </code> and therefore need not be
+ * caught separately, but if you are going to catch it separately, its
+ * catch block must appear before the more general <code> IOException </code>
+ * catch block.  When you encounter an
+ * {@link org.apache.commons.net.nntp.NNTPConnectionClosedException}
+ * , you must disconnect the connection with
+ * {@link #disconnect  disconnect() } to properly clean up the
+ * system resources used by NNTP.  Before disconnecting, you may check the
+ * last reply code and text with
+ * {@link #getReplyCode  getReplyCode } and
+ * {@link #getReplyString  getReplyString }.
+ * <p>
+ * Rather than list it separately for each method, we mention here that
+ * every method communicating with the server and throwing an IOException
+ * can also throw a
+ * {@link org.apache.commons.net.MalformedServerReplyException}
+ * , which is a subclass
+ * of IOException.  A MalformedServerReplyException will be thrown when
+ * the reply received from the server deviates enough from the protocol
+ * specification that it cannot be interpreted in a useful manner despite
+ * attempts to be as lenient as possible.
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ * @author Rory Winston
+ * @author Ted Wise
+ * @see NNTPClient
+ * @see NNTPConnectionClosedException
+ * @see org.apache.commons.net.MalformedServerReplyException
+ ***/
+
+public class NNTP extends SocketClient
+{
+    /*** The default NNTP port.  Its value is 119 according to RFC 977. ***/
+    public static final int DEFAULT_PORT = 119;
+
+    // We have to ensure that the protocol communication is in ASCII
+    // but we use ISO-8859-1 just in case 8-bit characters cross
+    // the wire.
+    private static final String __DEFAULT_ENCODING = "ISO-8859-1";
+
+    private StringBuffer __commandBuffer;
+
+    boolean _isAllowedToPost;
+    int _replyCode;
+    String _replyString;
+
+    /**
+     * Wraps {@link SocketClient#_input_}
+     * to communicate with server.  Initialized by {@link #_connectAction_}.
+     * All server reads should be done through this variable.
+     */
+    protected BufferedReader _reader_;
+
+    /**
+     * Wraps {@link SocketClient#_output_}
+     * to communicate with server.  Initialized by {@link #_connectAction_}.
+     * All server reads should be done through this variable.
+     */
+    protected BufferedWriter _writer_;
+
+    /***
+     * A ProtocolCommandSupport object used to manage the registering of
+     * ProtocolCommandListeners and te firing of ProtocolCommandEvents.
+     ***/
+    protected ProtocolCommandSupport _commandSupport_;
+
+    /***
+     * The default NNTP constructor.  Sets the default port to
+     * <code>DEFAULT_PORT</code> and initializes internal data structures
+     * for saving NNTP reply information.
+     ***/
+    public NNTP()
+    {
+        setDefaultPort(DEFAULT_PORT);
+        __commandBuffer = new StringBuffer();
+        _replyString = null;
+        _reader_ = null;
+        _writer_ = null;
+        _isAllowedToPost = false;
+        _commandSupport_ = new ProtocolCommandSupport(this);
+    }
+
+    private void __getReply() throws IOException
+    {
+        _replyString = _reader_.readLine();
+
+        if (_replyString == null)
+            throw new NNTPConnectionClosedException(
+                "Connection closed without indication.");
+
+        // In case we run into an anomaly we don't want fatal index exceptions
+        // to be thrown.
+        if (_replyString.length() < 3)
+            throw new MalformedServerReplyException(
+                "Truncated server reply: " + _replyString);
+        try
+        {
+            _replyCode = Integer.parseInt(_replyString.substring(0, 3));
+        }
+        catch (NumberFormatException e)
+        {
+            throw new MalformedServerReplyException(
+                "Could not parse response code.\nServer Reply: " + _replyString);
+        }
+
+        if (_commandSupport_.getListenerCount() > 0)
+            _commandSupport_.fireReplyReceived(_replyCode, _replyString +
+                                               SocketClient.NETASCII_EOL);
+
+        if (_replyCode == NNTPReply.SERVICE_DISCONTINUED)
+            throw new NNTPConnectionClosedException(
+                "NNTP response 400 received.  Server closed connection.");
+    }
+
+    /***
+     * Initiates control connections and gets initial reply, determining
+     * if the client is allowed to post to the server.  Initializes
+     * {@link #_reader_} and {@link #_writer_} to wrap
+     * {@link SocketClient#_input_} and {@link SocketClient#_output_}.
+     ***/
+    @Override
+    protected void _connectAction_() throws IOException
+    {
+        super._connectAction_();
+        _reader_ =
+            new BufferedReader(new InputStreamReader(_input_,
+                                                     __DEFAULT_ENCODING));
+        _writer_ =
+            new BufferedWriter(new OutputStreamWriter(_output_,
+                                                      __DEFAULT_ENCODING));
+        __getReply();
+
+        _isAllowedToPost = (_replyCode == NNTPReply.SERVER_READY_POSTING_ALLOWED);
+    }
+
+    /***
+     * Adds a ProtocolCommandListener.  Delegates this task to
+     * {@link #_commandSupport_  _commandSupport_ }.
+     * <p>
+     * @param listener  The ProtocolCommandListener to add.
+     ***/
+    public void addProtocolCommandListener(ProtocolCommandListener listener)
+    {
+        _commandSupport_.addProtocolCommandListener(listener);
+    }
+
+    /***
+     * Removes a ProtocolCommandListener.  Delegates this task to
+     * {@link #_commandSupport_  _commandSupport_ }.
+     * <p>
+     * @param listener  The ProtocolCommandListener to remove.
+     ***/
+    public void removeProtocolCommandListener(ProtocolCommandListener listener)
+    {
+        _commandSupport_.removeProtocolCommandListener(listener);
+    }
+
+    /***
+     * Closes the connection to the NNTP server and sets to null
+     * some internal data so that the memory may be reclaimed by the
+     * garbage collector.  The reply text and code information from the
+     * last command is voided so that the memory it used may be reclaimed.
+     * <p>
+     * @exception IOException If an error occurs while disconnecting.
+     ***/
+    @Override
+    public void disconnect() throws IOException
+    {
+        super.disconnect();
+        _reader_ = null;
+        _writer_ = null;
+        _replyString = null;
+        _isAllowedToPost = false;
+    }
+
+
+    /***
+     * Indicates whether or not the client is allowed to post articles to
+     * the server it is currently connected to.
+     * <p>
+     * @return True if the client can post articles to the server, false
+     *         otherwise.
+     ***/
+    public boolean isAllowedToPost()
+    {
+        return _isAllowedToPost;
+    }
+
+
+    /***
+     * Sends an NNTP command to the server, waits for a reply and returns the
+     * numerical response code.  After invocation, for more detailed
+     * information, the actual reply text can be accessed by calling
+     * {@link #getReplyString  getReplyString }.
+     * <p>
+     * @param command  The text representation of the  NNTP command to send.
+     * @param args The arguments to the NNTP command.  If this parameter is
+     *             set to null, then the command is sent with no argument.
+     * @return The integer value of the NNTP reply code returned by the server
+     *         in response to the command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int sendCommand(String command, String args) throws IOException
+    {
+        String message;
+
+        __commandBuffer.setLength(0);
+        __commandBuffer.append(command);
+
+        if (args != null)
+        {
+            __commandBuffer.append(' ');
+            __commandBuffer.append(args);
+        }
+        __commandBuffer.append(SocketClient.NETASCII_EOL);
+
+        _writer_.write(message = __commandBuffer.toString());
+        _writer_.flush();
+
+        if (_commandSupport_.getListenerCount() > 0)
+            _commandSupport_.fireCommandSent(command, message);
+
+        __getReply();
+        return _replyCode;
+    }
+
+
+    /***
+     * Sends an NNTP command to the server, waits for a reply and returns the
+     * numerical response code.  After invocation, for more detailed
+     * information, the actual reply text can be accessed by calling
+     * {@link #getReplyString  getReplyString }.
+     * <p>
+     * @param command  The NNTPCommand constant corresponding to the NNTP command
+     *                 to send.
+     * @param args The arguments to the NNTP command.  If this parameter is
+     *             set to null, then the command is sent with no argument.
+     * @return The integer value of the NNTP reply code returned by the server
+     *         in response to the command.
+     *         in response to the command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int sendCommand(int command, String args) throws IOException
+    {
+        return sendCommand(NNTPCommand._commands[command], args);
+    }
+
+
+    /***
+     * Sends an NNTP command with no arguments to the server, waits for a
+     * reply and returns the numerical response code.  After invocation, for
+     * more detailed information, the actual reply text can be accessed by
+     * calling {@link #getReplyString  getReplyString }.
+     * <p>
+     * @param command  The text representation of the  NNTP command to send.
+     * @return The integer value of the NNTP reply code returned by the server
+     *         in response to the command.
+     *         in response to the command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int sendCommand(String command) throws IOException
+    {
+        return sendCommand(command, null);
+    }
+
+
+    /***
+     * Sends an NNTP command with no arguments to the server, waits for a
+     * reply and returns the numerical response code.  After invocation, for
+     * more detailed information, the actual reply text can be accessed by
+     * calling {@link #getReplyString  getReplyString }.
+     * <p>
+     * @param command  The NNTPCommand constant corresponding to the NNTP command
+     *                 to send.
+     * @return The integer value of the NNTP reply code returned by the server
+     *         in response to the command.
+     *         in response to the command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int sendCommand(int command) throws IOException
+    {
+        return sendCommand(command, null);
+    }
+
+
+    /***
+     * Returns the integer value of the reply code of the last NNTP reply.
+     * You will usually only use this method after you connect to the
+     * NNTP server to check that the connection was successful since
+     * <code> connect </code> is of type void.
+     * <p>
+     * @return The integer value of the reply code of the last NNTP reply.
+     ***/
+    public int getReplyCode()
+    {
+        return _replyCode;
+    }
+
+    /***
+     * Fetches a reply from the NNTP server and returns the integer reply
+     * code.  After calling this method, the actual reply text can be accessed
+     * from {@link #getReplyString  getReplyString }.  Only use this
+     * method if you are implementing your own NNTP client or if you need to
+     * fetch a secondary response from the NNTP server.
+     * <p>
+     * @return The integer value of the reply code of the fetched NNTP reply.
+     *         in response to the command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while
+     *      receiving the server reply.
+     ***/
+    public int getReply() throws IOException
+    {
+        __getReply();
+        return _replyCode;
+    }
+
+
+    /***
+     * Returns the entire text of the last NNTP server response exactly
+     * as it was received, not including the end of line marker.
+     * <p>
+     * @return The entire text from the last NNTP response as a String.
+     ***/
+    public String getReplyString()
+    {
+        return _replyString;
+    }
+
+
+    /***
+     * A convenience method to send the NNTP ARTICLE command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param messageId  The message identifier of the requested article,
+     *                   including the encapsulating &lt and &gt characters.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int article(String messageId) throws IOException
+    {
+        return sendCommand(NNTPCommand.ARTICLE, messageId);
+    }
+
+    /***
+     * A convenience method to send the NNTP ARTICLE command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param articleNumber The number of the article to request from the
+     *                      currently selected newsgroup.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int article(int articleNumber) throws IOException
+    {
+        return sendCommand(NNTPCommand.ARTICLE, Integer.toString(articleNumber));
+    }
+
+    /***
+     * A convenience method to send the NNTP ARTICLE command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int article() throws IOException
+    {
+        return sendCommand(NNTPCommand.ARTICLE);
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP BODY command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param messageId  The message identifier of the requested article,
+     *                   including the encapsulating &lt and &gt characters.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int body(String messageId) throws IOException
+    {
+        return sendCommand(NNTPCommand.BODY, messageId);
+    }
+
+    /***
+     * A convenience method to send the NNTP BODY command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param articleNumber The number of the article to request from the
+     *                      currently selected newsgroup.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int body(int articleNumber) throws IOException
+    {
+        return sendCommand(NNTPCommand.BODY, Integer.toString(articleNumber));
+    }
+
+    /***
+     * A convenience method to send the NNTP BODY command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int body() throws IOException
+    {
+        return sendCommand(NNTPCommand.BODY);
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP HEAD command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param messageId  The message identifier of the requested article,
+     *                   including the encapsulating &lt and &gt characters.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int head(String messageId) throws IOException
+    {
+        return sendCommand(NNTPCommand.HEAD, messageId);
+    }
+
+    /***
+     * A convenience method to send the NNTP HEAD command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param articleNumber The number of the article to request from the
+     *                      currently selected newsgroup.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int head(int articleNumber) throws IOException
+    {
+        return sendCommand(NNTPCommand.HEAD, Integer.toString(articleNumber));
+    }
+
+    /***
+     * A convenience method to send the NNTP HEAD command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int head() throws IOException
+    {
+        return sendCommand(NNTPCommand.HEAD);
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP STAT command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param messageId  The message identifier of the requested article,
+     *                   including the encapsulating &lt and &gt characters.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int stat(String messageId) throws IOException
+    {
+        return sendCommand(NNTPCommand.STAT, messageId);
+    }
+
+    /***
+     * A convenience method to send the NNTP STAT command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @param articleNumber The number of the article to request from the
+     *                      currently selected newsgroup.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int stat(int articleNumber) throws IOException
+    {
+        return sendCommand(NNTPCommand.STAT, Integer.toString(articleNumber));
+    }
+
+    /***
+     * A convenience method to send the NNTP STAT command to the server,
+     * receive the initial reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int stat() throws IOException
+    {
+        return sendCommand(NNTPCommand.STAT);
+    }
+
+
+    /***
+     * A convenience method to send the NNTP GROUP command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @param newsgroup  The name of the newsgroup to select.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int group(String newsgroup) throws IOException
+    {
+        return sendCommand(NNTPCommand.GROUP, newsgroup);
+    }
+
+
+    /***
+     * A convenience method to send the NNTP HELP command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int help() throws IOException
+    {
+        return sendCommand(NNTPCommand.HELP);
+    }
+
+
+    /***
+     * A convenience method to send the NNTP IHAVE command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @param messageId  The article identifier,
+     *                   including the encapsulating &lt and &gt characters.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int ihave(String messageId) throws IOException
+    {
+        return sendCommand(NNTPCommand.IHAVE, messageId);
+    }
+
+
+    /***
+     * A convenience method to send the NNTP LAST command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int last() throws IOException
+    {
+        return sendCommand(NNTPCommand.LAST);
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP LIST command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int list() throws IOException
+    {
+        return sendCommand(NNTPCommand.LIST);
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP NEXT command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int next() throws IOException
+    {
+        return sendCommand(NNTPCommand.NEXT);
+    }
+
+
+    /***
+     * A convenience method to send the NNTP NEWGROUPS command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @param date The date after which to check for new groups.
+     *             Date format is YYMMDD
+     * @param time The time after which to check for new groups.
+     *             Time format is HHMMSS using a 24-hour clock.
+     * @param GMT  True if the time is in GMT, false if local server time.
+     * @param distributions  Comma-separated distribution list to check for
+     *            new groups. Set to null if no distributions.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int newgroups(String date, String time, boolean GMT,
+                         String distributions) throws IOException
+    {
+        StringBuffer buffer = new StringBuffer();
+
+        buffer.append(date);
+        buffer.append(' ');
+        buffer.append(time);
+
+        if (GMT)
+        {
+            buffer.append(' ');
+            buffer.append("GMT");
+        }
+
+        if (distributions != null)
+        {
+            buffer.append(" <");
+            buffer.append(distributions);
+            buffer.append('>');
+        }
+
+        return sendCommand(NNTPCommand.NEWGROUPS, buffer.toString());
+    }
+
+
+    /***
+     * A convenience method to send the NNTP NEWGROUPS command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @param newsgroups A comma-separated list of newsgroups to check for new
+     *             news.
+     * @param date The date after which to check for new news.
+     *             Date format is YYMMDD
+     * @param time The time after which to check for new news.
+     *             Time format is HHMMSS using a 24-hour clock.
+     * @param GMT  True if the time is in GMT, false if local server time.
+     * @param distributions  Comma-separated distribution list to check for
+     *            new news. Set to null if no distributions.
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int newnews(String newsgroups, String date, String time, boolean GMT,
+                       String distributions) throws IOException
+    {
+        StringBuffer buffer = new StringBuffer();
+
+        buffer.append(newsgroups);
+        buffer.append(' ');
+        buffer.append(date);
+        buffer.append(' ');
+        buffer.append(time);
+
+        if (GMT)
+        {
+            buffer.append(' ');
+            buffer.append("GMT");
+        }
+
+        if (distributions != null)
+        {
+            buffer.append(" <");
+            buffer.append(distributions);
+            buffer.append('>');
+        }
+
+        return sendCommand(NNTPCommand.NEWNEWS, buffer.toString());
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP POST command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int post() throws IOException
+    {
+        return sendCommand(NNTPCommand.POST);
+    }
+
+
+
+    /***
+     * A convenience method to send the NNTP QUIT command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int quit() throws IOException
+    {
+        return sendCommand(NNTPCommand.QUIT);
+    }
+
+    /***
+     * A convenience method to send the AUTHINFO USER command to the server,
+     *  receive the reply, and return the reply code. (See RFC 2980)
+     * <p>
+     * @param username A valid username.
+     * @return The reply code received from the server. The server should
+     *          return a 381 or 281 for this command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int authinfoUser(String username) throws IOException {
+        String userParameter = "USER " + username;
+        return sendCommand(NNTPCommand.AUTHINFO, userParameter);
+    }
+
+    /***
+     * A convenience method to send the AUTHINFO PASS command to the server,
+     * receive the reply, and return the reply code.  If this step is
+     * required, it should immediately follow the AUTHINFO USER command
+     * (See RFC 2980)
+     * <p>
+     * @param password a valid password.
+     * @return The reply code received from the server. The server should
+     *         return a 281 or 502 for this command.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int authinfoPass(String password) throws IOException {
+        String passParameter = "PASS " + password;
+        return sendCommand(NNTPCommand.AUTHINFO, passParameter);
+    }
+
+    /***
+     * A convenience method to send the NNTP XOVER command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @param selectedArticles a String representation of the range of
+     * article headers required. This may be an article number, or a
+     * range of article numbers in the form "XXXX-YYYY", where XXXX
+     * and YYYY are valid article numbers in the current group.  It
+     * also may be of the form "XXX-", meaning "return XXX and all
+     * following articles" In this revision, the last format is not
+     * possible (yet).
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int xover(String selectedArticles) throws IOException {
+        return sendCommand(NNTPCommand.XOVER, selectedArticles);
+    }
+
+    /***
+     * A convenience method to send the NNTP XHDR command to the server,
+     * receive the reply, and return the reply code.
+     * <p>
+     * @param header a String naming a header line (e.g., "subject").  See
+     * RFC-1036 for a list of valid header lines.
+     * @param selectedArticles a String representation of the range of
+     * article headers required. This may be an article number, or a
+     * range of article numbers in the form "XXXX-YYYY", where XXXX
+     * and YYYY are valid article numbers in the current group.  It
+     * also may be of the form "XXX-", meaning "return XXX and all
+     * following articles" In this revision, the last format is not
+     * possible (yet).
+     * @return The reply code received from the server.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending the
+     *      command or receiving the server reply.
+     ***/
+    public int xhdr(String header, String selectedArticles) throws IOException {
+        StringBuffer command = new StringBuffer(header);
+        command.append(" ");
+        command.append(selectedArticles);
+        return sendCommand(NNTPCommand.XHDR, command.toString());
+    }
+
+    /**
+     * A convenience wrapper for the extended LIST command that takes
+     * an argument, allowing us to selectively list multiple groups.
+     * <p>
+     * @param wildmat A wildmat (pseudo-regex) pattern. See RFC 2980 for
+     *                details.
+     * @return the reply code received from the server.
+     * @throws IOException
+     */
+    public int listActive(String wildmat) throws IOException {
+        StringBuffer command = new StringBuffer("ACTIVE ");
+        command.append(wildmat);
+        return sendCommand(NNTPCommand.LIST, command.toString());
+    }
+}
+
+/* Emacs configuration
+ * Local variables:        **
+ * mode:             java  **
+ * c-basic-offset:   4     **
+ * indent-tabs-mode: nil   **
+ * End:                    **
+ */
diff --git a/org/apache/commons/net/nntp/NNTPClient.java b/org/apache/commons/net/nntp/NNTPClient.java
new file mode 100644
index 0000000..e10ce90
--- /dev/null
+++ b/org/apache/commons/net/nntp/NNTPClient.java
@@ -0,0 +1,1285 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.StringWriter;
+import java.io.Writer;
+import java.util.StringTokenizer;
+import java.util.Vector;
+
+import org.apache.commons.net.MalformedServerReplyException;
+import org.apache.commons.net.io.DotTerminatedMessageReader;
+import org.apache.commons.net.io.DotTerminatedMessageWriter;
+import org.apache.commons.net.io.Util;
+
+/***
+ * NNTPClient encapsulates all the functionality necessary to post and
+ * retrieve articles from an NNTP server.  As with all classes derived
+ * from {@link org.apache.commons.net.SocketClient},
+ * you must first connect to the server with
+ * {@link org.apache.commons.net.SocketClient#connect  connect }
+ * before doing anything, and finally
+ * {@link org.apache.commons.net.nntp.NNTP#disconnect  disconnect() }
+ * after you're completely finished interacting with the server.
+ * Remember that the
+ * {@link org.apache.commons.net.nntp.NNTP#isAllowedToPost isAllowedToPost()}
+ *  method is defined in
+ * {@link org.apache.commons.net.nntp.NNTP}.
+ * <p>
+ * You should keep in mind that the NNTP server may choose to prematurely
+ * close a connection if the client has been idle for longer than a
+ * given time period or if the server is being shutdown by the operator or
+ * some other reason.  The NNTP class will detect a
+ * premature NNTP server connection closing when it receives a
+ * {@link org.apache.commons.net.nntp.NNTPReply#SERVICE_DISCONTINUED NNTPReply.SERVICE_DISCONTINUED }
+ *  response to a command.
+ * When that occurs, the NNTP class method encountering that reply will throw
+ * an {@link org.apache.commons.net.nntp.NNTPConnectionClosedException}
+ * .
+ * <code>NNTPConectionClosedException</code>
+ * is a subclass of <code> IOException </code> and therefore need not be
+ * caught separately, but if you are going to catch it separately, its
+ * catch block must appear before the more general <code> IOException </code>
+ * catch block.  When you encounter an
+ * {@link org.apache.commons.net.nntp.NNTPConnectionClosedException}
+ * , you must disconnect the connection with
+ * {@link org.apache.commons.net.nntp.NNTP#disconnect  disconnect() }
+ *  to properly clean up the
+ * system resources used by NNTP.  Before disconnecting, you may check the
+ * last reply code and text with
+ * {@link org.apache.commons.net.nntp.NNTP#getReplyCode  getReplyCode } and
+ * {@link org.apache.commons.net.nntp.NNTP#getReplyString  getReplyString }.
+ * <p>
+ * Rather than list it separately for each method, we mention here that
+ * every method communicating with the server and throwing an IOException
+ * can also throw a
+ * {@link org.apache.commons.net.MalformedServerReplyException}
+ * , which is a subclass
+ * of IOException.  A MalformedServerReplyException will be thrown when
+ * the reply received from the server deviates enough from the protocol
+ * specification that it cannot be interpreted in a useful manner despite
+ * attempts to be as lenient as possible.
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ * @author Rory Winston
+ * @author Ted Wise
+ * @see NNTP
+ * @see NNTPConnectionClosedException
+ * @see org.apache.commons.net.MalformedServerReplyException
+ ***/
+
+public class NNTPClient extends NNTP
+{
+
+    private void __parseArticlePointer(String reply, ArticlePointer pointer)
+    throws MalformedServerReplyException
+    {
+        StringTokenizer tokenizer;
+
+        // Do loop is a kluge to simulate goto
+        do
+        {
+            tokenizer = new StringTokenizer(reply);
+
+            if (tokenizer.countTokens() < 3)
+                break;
+
+            // Skip numeric response value
+            tokenizer.nextToken();
+            // Get article number
+            try
+            {
+                pointer.articleNumber = Integer.parseInt(tokenizer.nextToken());
+            }
+            catch (NumberFormatException e)
+            {
+                break;
+            }
+
+            // Get article id
+            pointer.articleId = tokenizer.nextToken();
+            return ;
+        }
+        while (false);
+
+        throw new MalformedServerReplyException(
+            "Could not parse article pointer.\nServer reply: " + reply);
+    }
+
+
+    private void __parseGroupReply(String reply, NewsgroupInfo info)
+    throws MalformedServerReplyException
+    {
+        String count, first, last;
+        StringTokenizer tokenizer;
+
+        // Do loop is a kluge to simulate goto
+        do
+        {
+            tokenizer = new StringTokenizer(reply);
+
+            if (tokenizer.countTokens() < 5)
+                break;
+
+            // Skip numeric response value
+            tokenizer.nextToken();
+            // Get estimated article count
+            count = tokenizer.nextToken();
+            // Get first article number
+            first = tokenizer.nextToken();
+            // Get last article number
+            last = tokenizer.nextToken();
+            // Get newsgroup name
+            info._setNewsgroup(tokenizer.nextToken());
+
+            try
+            {
+                info._setArticleCount(Integer.parseInt(count));
+                info._setFirstArticle(Integer.parseInt(first));
+                info._setLastArticle(Integer.parseInt(last));
+            }
+            catch (NumberFormatException e)
+            {
+                break;
+            }
+
+            info._setPostingPermission(NewsgroupInfo.UNKNOWN_POSTING_PERMISSION);
+            return ;
+        }
+        while (false);
+
+        throw new MalformedServerReplyException(
+            "Could not parse newsgroup info.\nServer reply: " + reply);
+    }
+
+
+    private NewsgroupInfo __parseNewsgroupListEntry(String entry)
+    {
+        NewsgroupInfo result;
+        StringTokenizer tokenizer;
+        int lastNum, firstNum;
+        String last, first, permission;
+
+        result = new NewsgroupInfo();
+        tokenizer = new StringTokenizer(entry);
+
+        if (tokenizer.countTokens() < 4)
+            return null;
+
+        result._setNewsgroup(tokenizer.nextToken());
+        last = tokenizer.nextToken();
+        first = tokenizer.nextToken();
+        permission = tokenizer.nextToken();
+
+        try
+        {
+            lastNum = Integer.parseInt(last);
+            firstNum = Integer.parseInt(first);
+            result._setFirstArticle(firstNum);
+            result._setLastArticle(lastNum);
+
+        if((firstNum == 0) && (lastNum == 0))
+            result._setArticleCount(0);
+        else
+            result._setArticleCount(lastNum - firstNum + 1);
+        }
+        catch (NumberFormatException e)
+        {
+            return null;
+        }
+
+        switch (permission.charAt(0))
+        {
+        case 'y':
+        case 'Y':
+            result._setPostingPermission(
+                NewsgroupInfo.PERMITTED_POSTING_PERMISSION);
+            break;
+        case 'n':
+        case 'N':
+            result._setPostingPermission(
+                NewsgroupInfo.PROHIBITED_POSTING_PERMISSION);
+            break;
+        case 'm':
+        case 'M':
+            result._setPostingPermission(
+                NewsgroupInfo.MODERATED_POSTING_PERMISSION);
+            break;
+        default:
+            result._setPostingPermission(
+                NewsgroupInfo.UNKNOWN_POSTING_PERMISSION);
+            break;
+        }
+
+        return result;
+    }
+
+    private NewsgroupInfo[] __readNewsgroupListing() throws IOException
+    {
+        int size;
+        String line;
+        Vector<NewsgroupInfo> list;
+        BufferedReader reader;
+        NewsgroupInfo tmp, info[];
+
+        reader = new BufferedReader(new DotTerminatedMessageReader(_reader_));
+        // Start of with a big vector because we may be reading a very large
+        // amount of groups.
+        list = new Vector<NewsgroupInfo>(2048);
+
+        while ((line = reader.readLine()) != null)
+        {
+            tmp = __parseNewsgroupListEntry(line);
+            if (tmp != null)
+                list.addElement(tmp);
+            else
+                throw new MalformedServerReplyException(line);
+        }
+
+        if ((size = list.size()) < 1)
+            return new NewsgroupInfo[0];
+
+        info = new NewsgroupInfo[size];
+        list.copyInto(info);
+
+        return info;
+    }
+
+
+    private Reader __retrieve(int command,
+                              String articleId, ArticlePointer pointer)
+    throws IOException
+    {
+        Reader reader;
+
+        if (articleId != null)
+        {
+            if (!NNTPReply.isPositiveCompletion(sendCommand(command, articleId)))
+                return null;
+        }
+        else
+        {
+            if (!NNTPReply.isPositiveCompletion(sendCommand(command)))
+                return null;
+        }
+
+
+        if (pointer != null)
+            __parseArticlePointer(getReplyString(), pointer);
+
+        reader = new DotTerminatedMessageReader(_reader_);
+        return reader;
+    }
+
+
+    private Reader __retrieve(int command,
+                              int articleNumber, ArticlePointer pointer)
+    throws IOException
+    {
+        Reader reader;
+
+        if (!NNTPReply.isPositiveCompletion(sendCommand(command,
+                                            Integer.toString(articleNumber))))
+            return null;
+
+        if (pointer != null)
+            __parseArticlePointer(getReplyString(), pointer);
+
+        reader = new DotTerminatedMessageReader(_reader_);
+        return reader;
+    }
+
+
+
+    /***
+     * Retrieves an article from the NNTP server.  The article is referenced
+     * by its unique article identifier (including the enclosing &lt and &gt).
+     * The article number and identifier contained in the server reply
+     * are returned through an ArticlePointer.  The <code> articleId </code>
+     * field of the ArticlePointer cannot always be trusted because some
+     * NNTP servers do not correctly follow the RFC 977 reply format.
+     * <p>
+     * A DotTerminatedMessageReader is returned from which the article can
+     * be read.  If the article does not exist, null is returned.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * other methods) until you finish reading the message from the returned
+     * Reader instance.
+     * The NNTP protocol uses the same stream for issuing commands as it does
+     * for returning results.  Therefore the returned Reader actually reads
+     * directly from the NNTP connection.  After the end of message has been
+     * reached, new commands can be executed and their replies read.  If
+     * you do not follow these requirements, your program will not work
+     * properly.
+     * <p>
+     * @param articleId  The unique article identifier of the article to
+     *     retrieve.  If this parameter is null, the currently selected
+     *     article is retrieved.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return A DotTerminatedMessageReader instance from which the article
+     *         be read.  null if the article does not exist.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public Reader retrieveArticle(String articleId, ArticlePointer pointer)
+    throws IOException
+    {
+        return __retrieve(NNTPCommand.ARTICLE, articleId, pointer);
+
+    }
+
+    /*** Same as <code> retrieveArticle(articleId, null) </code> ***/
+    public Reader retrieveArticle(String articleId) throws IOException
+    {
+        return retrieveArticle(articleId, null);
+    }
+
+    /*** Same as <code> retrieveArticle(null) </code> ***/
+    public Reader retrieveArticle() throws IOException
+    {
+        return retrieveArticle(null);
+    }
+
+
+    /***
+     * Retrieves an article from the currently selected newsgroup.  The
+     * article is referenced by its article number.
+     * The article number and identifier contained in the server reply
+     * are returned through an ArticlePointer.  The <code> articleId </code>
+     * field of the ArticlePointer cannot always be trusted because some
+     * NNTP servers do not correctly follow the RFC 977 reply format.
+     * <p>
+     * A DotTerminatedMessageReader is returned from which the article can
+     * be read.  If the article does not exist, null is returned.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * other methods) until you finish reading the message from the returned
+     * Reader instance.
+     * The NNTP protocol uses the same stream for issuing commands as it does
+     * for returning results.  Therefore the returned Reader actually reads
+     * directly from the NNTP connection.  After the end of message has been
+     * reached, new commands can be executed and their replies read.  If
+     * you do not follow these requirements, your program will not work
+     * properly.
+     * <p>
+     * @param articleNumber  The number of the the article to
+     *     retrieve.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return A DotTerminatedMessageReader instance from which the article
+     *         be read.  null if the article does not exist.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public Reader retrieveArticle(int articleNumber, ArticlePointer pointer)
+    throws IOException
+    {
+        return __retrieve(NNTPCommand.ARTICLE, articleNumber, pointer);
+    }
+
+    /*** Same as <code> retrieveArticle(articleNumber, null) </code> ***/
+    public Reader retrieveArticle(int articleNumber) throws IOException
+    {
+        return retrieveArticle(articleNumber, null);
+    }
+
+
+
+    /***
+     * Retrieves an article header from the NNTP server.  The article is
+     * referenced
+     * by its unique article identifier (including the enclosing &lt and &gt).
+     * The article number and identifier contained in the server reply
+     * are returned through an ArticlePointer.  The <code> articleId </code>
+     * field of the ArticlePointer cannot always be trusted because some
+     * NNTP servers do not correctly follow the RFC 977 reply format.
+     * <p>
+     * A DotTerminatedMessageReader is returned from which the article can
+     * be read.  If the article does not exist, null is returned.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * other methods) until you finish reading the message from the returned
+     * Reader instance.
+     * The NNTP protocol uses the same stream for issuing commands as it does
+     * for returning results.  Therefore the returned Reader actually reads
+     * directly from the NNTP connection.  After the end of message has been
+     * reached, new commands can be executed and their replies read.  If
+     * you do not follow these requirements, your program will not work
+     * properly.
+     * <p>
+     * @param articleId  The unique article identifier of the article whose
+     *    header is being retrieved.  If this parameter is null, the
+     *    header of the currently selected article is retrieved.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return A DotTerminatedMessageReader instance from which the article
+     *         header can be read.  null if the article does not exist.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public Reader retrieveArticleHeader(String articleId, ArticlePointer pointer)
+    throws IOException
+    {
+        return __retrieve(NNTPCommand.HEAD, articleId, pointer);
+
+    }
+
+    /*** Same as <code> retrieveArticleHeader(articleId, null) </code> ***/
+    public Reader retrieveArticleHeader(String articleId) throws IOException
+    {
+        return retrieveArticleHeader(articleId, null);
+    }
+
+    /*** Same as <code> retrieveArticleHeader(null) </code> ***/
+    public Reader retrieveArticleHeader() throws IOException
+    {
+        return retrieveArticleHeader(null);
+    }
+
+
+    /***
+     * Retrieves an article header from the currently selected newsgroup.  The
+     * article is referenced by its article number.
+     * The article number and identifier contained in the server reply
+     * are returned through an ArticlePointer.  The <code> articleId </code>
+     * field of the ArticlePointer cannot always be trusted because some
+     * NNTP servers do not correctly follow the RFC 977 reply format.
+     * <p>
+     * A DotTerminatedMessageReader is returned from which the article can
+     * be read.  If the article does not exist, null is returned.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * other methods) until you finish reading the message from the returned
+     * Reader instance.
+     * The NNTP protocol uses the same stream for issuing commands as it does
+     * for returning results.  Therefore the returned Reader actually reads
+     * directly from the NNTP connection.  After the end of message has been
+     * reached, new commands can be executed and their replies read.  If
+     * you do not follow these requirements, your program will not work
+     * properly.
+     * <p>
+     * @param articleNumber  The number of the the article whose header is
+     *     being retrieved.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return A DotTerminatedMessageReader instance from which the article
+     *         header can be read.  null if the article does not exist.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public Reader retrieveArticleHeader(int articleNumber,
+                                        ArticlePointer pointer)
+    throws IOException
+    {
+        return __retrieve(NNTPCommand.HEAD, articleNumber, pointer);
+    }
+
+
+    /*** Same as <code> retrieveArticleHeader(articleNumber, null) </code> ***/
+    public Reader retrieveArticleHeader(int articleNumber) throws IOException
+    {
+        return retrieveArticleHeader(articleNumber, null);
+    }
+
+
+
+    /***
+     * Retrieves an article body from the NNTP server.  The article is
+     * referenced
+     * by its unique article identifier (including the enclosing &lt and &gt).
+     * The article number and identifier contained in the server reply
+     * are returned through an ArticlePointer.  The <code> articleId </code>
+     * field of the ArticlePointer cannot always be trusted because some
+     * NNTP servers do not correctly follow the RFC 977 reply format.
+     * <p>
+     * A DotTerminatedMessageReader is returned from which the article can
+     * be read.  If the article does not exist, null is returned.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * other methods) until you finish reading the message from the returned
+     * Reader instance.
+     * The NNTP protocol uses the same stream for issuing commands as it does
+     * for returning results.  Therefore the returned Reader actually reads
+     * directly from the NNTP connection.  After the end of message has been
+     * reached, new commands can be executed and their replies read.  If
+     * you do not follow these requirements, your program will not work
+     * properly.
+     * <p>
+     * @param articleId  The unique article identifier of the article whose
+     *    body is being retrieved.  If this parameter is null, the
+     *    body of the currently selected article is retrieved.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return A DotTerminatedMessageReader instance from which the article
+     *         body can be read.  null if the article does not exist.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public Reader retrieveArticleBody(String articleId, ArticlePointer pointer)
+    throws IOException
+    {
+        return __retrieve(NNTPCommand.BODY, articleId, pointer);
+
+    }
+
+    /*** Same as <code> retrieveArticleBody(articleId, null) </code> ***/
+    public Reader retrieveArticleBody(String articleId) throws IOException
+    {
+        return retrieveArticleBody(articleId, null);
+    }
+
+    /*** Same as <code> retrieveArticleBody(null) </code> ***/
+    public Reader retrieveArticleBody() throws IOException
+    {
+        return retrieveArticleBody(null);
+    }
+
+
+    /***
+     * Retrieves an article body from the currently selected newsgroup.  The
+     * article is referenced by its article number.
+     * The article number and identifier contained in the server reply
+     * are returned through an ArticlePointer.  The <code> articleId </code>
+     * field of the ArticlePointer cannot always be trusted because some
+     * NNTP servers do not correctly follow the RFC 977 reply format.
+     * <p>
+     * A DotTerminatedMessageReader is returned from which the article can
+     * be read.  If the article does not exist, null is returned.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * other methods) until you finish reading the message from the returned
+     * Reader instance.
+     * The NNTP protocol uses the same stream for issuing commands as it does
+     * for returning results.  Therefore the returned Reader actually reads
+     * directly from the NNTP connection.  After the end of message has been
+     * reached, new commands can be executed and their replies read.  If
+     * you do not follow these requirements, your program will not work
+     * properly.
+     * <p>
+     * @param articleNumber  The number of the the article whose body is
+     *     being retrieved.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return A DotTerminatedMessageReader instance from which the article
+     *         body can be read.  null if the article does not exist.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public Reader retrieveArticleBody(int articleNumber,
+                                      ArticlePointer pointer)
+    throws IOException
+    {
+        return __retrieve(NNTPCommand.BODY, articleNumber, pointer);
+    }
+
+
+    /*** Same as <code> retrieveArticleBody(articleNumber, null) </code> ***/
+    public Reader retrieveArticleBody(int articleNumber) throws IOException
+    {
+        return retrieveArticleBody(articleNumber, null);
+    }
+
+
+    /***
+     * Select the specified newsgroup to be the target of for future article
+     * retrieval and posting operations.  Also return the newsgroup
+     * information contained in the server reply through the info parameter.
+     * <p>
+     * @param newsgroup  The newsgroup to select.
+     * @param info  A parameter through which the newsgroup information of
+     *      the selected newsgroup contained in the server reply is returned.
+     *      Set this to null if you do not desire this information.
+     * @return True if the newsgroup exists and was selected, false otherwise.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean selectNewsgroup(String newsgroup, NewsgroupInfo info)
+    throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(group(newsgroup)))
+            return false;
+
+        if (info != null)
+            __parseGroupReply(getReplyString(), info);
+
+        return true;
+    }
+
+    /*** Same as <code> selectNewsgroup(newsgroup, null) </code> ***/
+    public boolean selectNewsgroup(String newsgroup) throws IOException
+    {
+        return selectNewsgroup(newsgroup, null);
+    }
+
+    /***
+     * List the command help from the server.
+     * <p>
+     * @return The sever help information.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public String listHelp() throws IOException
+    {
+        StringWriter help;
+        Reader reader;
+
+        if (!NNTPReply.isInformational(help()))
+            return null;
+
+        help = new StringWriter();
+        reader = new DotTerminatedMessageReader(_reader_);
+        Util.copyReader(reader, help);
+        reader.close();
+        help.close();
+        return help.toString();
+    }
+
+
+    /***
+     * Select an article by its unique identifier (including enclosing
+     * &lt and &gt) and return its article number and id through the
+     * pointer parameter.  This is achieved through the STAT command.
+     * According to RFC 977, this will NOT set the current article pointer
+     * on the server.  To do that, you must reference the article by its
+     * number.
+     * <p>
+     * @param articleId  The unique article identifier of the article that
+     *    is being selectedd.  If this parameter is null, the
+     *    body of the current article is selected
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return True if successful, false if not.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean selectArticle(String articleId, ArticlePointer pointer)
+    throws IOException
+    {
+        if (articleId != null)
+        {
+            if (!NNTPReply.isPositiveCompletion(stat(articleId)))
+                return false;
+        }
+        else
+        {
+            if (!NNTPReply.isPositiveCompletion(stat()))
+                return false;
+        }
+
+        if (pointer != null)
+            __parseArticlePointer(getReplyString(), pointer);
+
+        return true;
+    }
+
+    /**** Same as <code> selectArticle(articleId, null) </code> ***/
+    public boolean selectArticle(String articleId) throws IOException
+    {
+        return selectArticle(articleId, null);
+    }
+
+    /****
+     * Same as <code> selectArticle(null, articleId) </code>.  Useful
+     * for retrieving the current article number.
+     ***/
+    public boolean selectArticle(ArticlePointer pointer) throws IOException
+    {
+        return selectArticle(null, pointer);
+    }
+
+
+    /***
+     * Select an article in the currently selected newsgroup by its number.
+     * and return its article number and id through the
+     * pointer parameter.  This is achieved through the STAT command.
+     * According to RFC 977, this WILL set the current article pointer
+     * on the server.  Use this command to select an article before retrieving
+     * it, or to obtain an article's unique identifier given its number.
+     * <p>
+     * @param articleNumber The number of the article to select from the
+     *       currently selected newsgroup.
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  Although the articleId field cannot always
+     *   be trusted because of server deviations from RFC 977 reply formats,
+     *   we haven't found a server that misformats this information in response
+     *   to this particular command.  You may set this parameter to null if
+     *   you do not desire to retrieve the returned article information.
+     * @return True if successful, false if not.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean selectArticle(int articleNumber, ArticlePointer pointer)
+    throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(stat(articleNumber)))
+            return false;
+
+        if (pointer != null)
+            __parseArticlePointer(getReplyString(), pointer);
+
+        return true;
+    }
+
+
+    /*** Same as <code> selectArticle(articleNumber, null) </code> ***/
+    public boolean selectArticle(int articleNumber) throws IOException
+    {
+        return selectArticle(articleNumber, null);
+    }
+
+
+    /***
+     * Select the article preceeding the currently selected article in the
+     * currently selected newsgroup and return its number and unique id
+     * through the pointer parameter.  Because of deviating server
+     * implementations, the articleId information cannot be trusted.  To
+     * obtain the article identifier, issue a
+     * <code> selectArticle(pointer.articleNumber, pointer) </code> immediately
+     * afterward.
+     * <p>
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return True if successful, false if not (e.g., there is no previous
+     *     article).
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean selectPreviousArticle(ArticlePointer pointer)
+    throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(last()))
+            return false;
+
+        if (pointer != null)
+            __parseArticlePointer(getReplyString(), pointer);
+
+        return true;
+    }
+
+    /*** Same as <code> selectPreviousArticle(null) </code> ***/
+    public boolean selectPreviousArticle() throws IOException
+    {
+        return selectPreviousArticle(null);
+    }
+
+
+    /***
+     * Select the article following the currently selected article in the
+     * currently selected newsgroup and return its number and unique id
+     * through the pointer parameter.  Because of deviating server
+     * implementations, the articleId information cannot be trusted.  To
+     * obtain the article identifier, issue a
+     * <code> selectArticle(pointer.articleNumber, pointer) </code> immediately
+     * afterward.
+     * <p>
+     * @param pointer    A parameter through which to return the article's
+     *   number and unique id.  The articleId field cannot always be trusted
+     *   because of server deviations from RFC 977 reply formats.  You may
+     *   set this parameter to null if you do not desire to retrieve the
+     *   returned article information.
+     * @return True if successful, false if not (e.g., there is no following
+     *         article).
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean selectNextArticle(ArticlePointer pointer) throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(next()))
+            return false;
+
+        if (pointer != null)
+            __parseArticlePointer(getReplyString(), pointer);
+
+        return true;
+    }
+
+
+    /*** Same as <code> selectNextArticle(null) </code> ***/
+    public boolean selectNextArticle() throws IOException
+    {
+        return selectNextArticle(null);
+    }
+
+
+    /***
+     * List all newsgroups served by the NNTP server.  If no newsgroups
+     * are served, a zero length array will be returned.  If the command
+     * fails, null will be returned.
+     * <p>
+     * @return An array of NewsgroupInfo instances containing the information
+     *    for each newsgroup served by the NNTP server.   If no newsgroups
+     *    are served, a zero length array will be returned.  If the command
+     *    fails, null will be returned.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public NewsgroupInfo[] listNewsgroups() throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(list()))
+            return null;
+
+        return __readNewsgroupListing();
+    }
+
+    /**
+     * An overloaded listNewsgroups() command that allows us to
+     * specify with a pattern what groups we want to list. Wraps the
+     * LIST ACTIVE command.
+     * <p>
+     * @param wildmat a pseudo-regex pattern (cf. RFC 2980)
+     * @return An array of NewsgroupInfo instances containing the information
+     *    for each newsgroup served by the NNTP server corresponding to the
+     *    supplied pattern.   If no such newsgroups are served, a zero length
+     *    array will be returned.  If the command fails, null will be returned.
+     * @throws IOException
+     */
+    public NewsgroupInfo[] listNewsgroups(String wildmat) throws IOException
+    {
+        if(!NNTPReply.isPositiveCompletion(listActive(wildmat)))
+            return null;
+        return __readNewsgroupListing();
+    }
+
+
+    /***
+     * List all new newsgroups added to the NNTP server since a particular
+     * date subject to the conditions of the specified query.  If no new
+     * newsgroups were added, a zero length array will be returned.  If the
+     * command fails, null will be returned.
+     * <p>
+     * @param query  The query restricting how to search for new newsgroups.
+     * @return An array of NewsgroupInfo instances containing the information
+     *    for each new newsgroup added to the NNTP server.   If no newsgroups
+     *    were added, a zero length array will be returned.  If the command
+     *    fails, null will be returned.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public NewsgroupInfo[] listNewNewsgroups(NewGroupsOrNewsQuery query)
+    throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(newgroups(
+                                                query.getDate(), query.getTime(),
+                                                query.isGMT(), query.getDistributions())))
+            return null;
+
+        return __readNewsgroupListing();
+    }
+
+
+    /***
+     * List all new articles added to the NNTP server since a particular
+     * date subject to the conditions of the specified query.  If no new
+     * new news is found, a zero length array will be returned.  If the
+     * command fails, null will be returned.  You must add at least one
+     * newsgroup to the query, else the command will fail.  Each String
+     * in the returned array is a unique message identifier including the
+     * enclosing &lt and &gt.
+     * <p>
+     * @param query  The query restricting how to search for new news.  You
+     *    must add at least one newsgroup to the query.
+     * @return An array of String instances containing the unique message
+     *    identifiers for each new article added to the NNTP server.  If no
+     *    new news is found, a zero length array will be returned.  If the
+     *    command fails, null will be returned.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public String[] listNewNews(NewGroupsOrNewsQuery query)
+    throws IOException
+    {
+        int size;
+        String line;
+        Vector<String> list;
+        String[] result;
+        BufferedReader reader;
+
+        if (!NNTPReply.isPositiveCompletion(newnews(
+                                                query.getNewsgroups(), query.getDate(), query.getTime(),
+                                                query.isGMT(), query.getDistributions())))
+            return null;
+
+        list = new Vector<String>();
+        reader = new BufferedReader(new DotTerminatedMessageReader(_reader_));
+
+        while ((line = reader.readLine()) != null)
+            list.addElement(line);
+
+        size = list.size();
+
+        if (size < 1)
+            return new String[0];
+
+        result = new String[size];
+        list.copyInto(result);
+
+        return result;
+    }
+
+    /***
+     * There are a few NNTPClient methods that do not complete the
+     * entire sequence of NNTP commands to complete a transaction.  These
+     * commands require some action by the programmer after the reception
+     * of a positive preliminary command.  After the programmer's code
+     * completes its actions, it must call this method to receive
+     * the completion reply from the server and verify the success of the
+     * entire transaction.
+     * <p>
+     * For example
+     * <pre>
+     * writer = client.postArticle();
+     * if(writer == null) // failure
+     *   return false;
+     * header = new SimpleNNTPHeader("foobar@foo.com", "Just testing");
+     * header.addNewsgroup("alt.test");
+     * writer.write(header.toString());
+     * writer.write("This is just a test");
+     * writer.close();
+     * if(!client.completePendingCommand()) // failure
+     *   return false;
+     * </pre>
+     * <p>
+     * @return True if successfully completed, false if not.
+     * @exception NNTPConnectionClosedException
+     *      If the NNTP server prematurely closes the connection as a result
+     *      of the client being idle or some other reason causing the server
+     *      to send NNTP reply code 400.  This exception may be caught either
+     *      as an IOException or independently as itself.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean completePendingCommand() throws IOException
+    {
+        return NNTPReply.isPositiveCompletion(getReply());
+    }
+
+    /***
+     * Post an article to the NNTP server.  This method returns a
+     * DotTerminatedMessageWriter instance to which the article can be
+     * written.  Null is returned if the posting attempt fails.  You
+     * should check {@link NNTP#isAllowedToPost isAllowedToPost() }
+     *  before trying to post.  However, a posting
+     * attempt can fail due to malformed headers.
+     * <p>
+     * You must not issue any commands to the NNTP server (i.e., call any
+     * (other methods) until you finish writing to the returned Writer
+     * instance and close it.  The NNTP protocol uses the same stream for
+     * issuing commands as it does for returning results.  Therefore the
+     * returned Writer actually writes directly to the NNTP connection.
+     * After you close the writer, you can execute new commands.  If you
+     * do not follow these requirements your program will not work properly.
+     * <p>
+     * Different NNTP servers will require different header formats, but
+     * you can use the provided
+     * {@link org.apache.commons.net.nntp.SimpleNNTPHeader}
+     * class to construct the bare minimum acceptable header for most
+     * news readers.  To construct more complicated headers you should
+     * refer to RFC 822.  When the Java Mail API is finalized, you will be
+     * able to use it to compose fully compliant Internet text messages.
+     * The DotTerminatedMessageWriter takes care of doubling line-leading
+     * dots and ending the message with a single dot upon closing, so all
+     * you have to worry about is writing the header and the message.
+     * <p>
+     * Upon closing the returned Writer, you need to call
+     * {@link #completePendingCommand  completePendingCommand() }
+     * to finalize the posting and verify its success or failure from
+     * the server reply.
+     * <p>
+     * @return A DotTerminatedMessageWriter to which the article (including
+     *      header) can be written.  Returns null if the command fails.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+
+    public Writer postArticle() throws IOException
+    {
+        if (!NNTPReply.isPositiveIntermediate(post()))
+            return null;
+
+        return new DotTerminatedMessageWriter(_writer_);
+    }
+
+
+    public Writer forwardArticle(String articleId) throws IOException
+    {
+        if (!NNTPReply.isPositiveIntermediate(ihave(articleId)))
+            return null;
+
+        return new DotTerminatedMessageWriter(_writer_);
+    }
+
+
+    /***
+     * Logs out of the news server gracefully by sending the QUIT command.
+     * However, you must still disconnect from the server before you can open
+     * a new connection.
+     * <p>
+     * @return True if successfully completed, false if not.
+     * @exception IOException  If an I/O error occurs while either sending a
+     *      command to the server or receiving a reply from the server.
+     ***/
+    public boolean logout() throws IOException
+    {
+        return NNTPReply.isPositiveCompletion(quit());
+    }
+
+
+    /**
+     * Log into a news server by sending the AUTHINFO USER/AUTHINFO
+     * PASS command sequence. This is usually sent in response to a
+     * 480 reply code from the NNTP server.
+     * <p>
+     * @param username a valid username
+     * @param password the corresponding password
+     * @return True for successful login, false for a failure
+     * @throws IOException
+     */
+    public boolean authenticate(String username, String password)
+        throws IOException
+    {
+        int replyCode = authinfoUser(username);
+
+        if (replyCode == NNTPReply.MORE_AUTH_INFO_REQUIRED)
+            {
+                replyCode = authinfoPass(password);
+
+                if (replyCode == NNTPReply.AUTHENTICATION_ACCEPTED)
+                    {
+                        _isAllowedToPost = true;
+                        return true;
+                    }
+            }
+        return false;
+    }
+
+    /***
+     * Private implementation of XOVER functionality.
+     *
+     * See {@link NNTP#xover}
+     * for legal agument formats. Alternatively, read RFC 2980 :-)
+     * <p>
+     * @param articleRange
+     * @return Returns a DotTerminatedMessageReader if successful, null
+     *         otherwise
+     * @exception IOException
+     */
+    private Reader __retrieveArticleInfo(String articleRange)
+        throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(xover(articleRange)))
+            return null;
+
+        return new DotTerminatedMessageReader(_reader_);
+    }
+
+    /**
+     * Return article headers for a specified post.
+     * <p>
+     * @param articleNumber the article to retrieve headers for
+     * @return a DotTerminatedReader if successful, null otherwise
+     * @throws IOException
+     */
+    public Reader retrieveArticleInfo(int articleNumber) throws IOException
+    {
+        return __retrieveArticleInfo(Integer.toString(articleNumber));
+    }
+
+    /**
+     * Return article headers for all articles between lowArticleNumber
+     * and highArticleNumber, inclusively.
+     * <p>
+     * @param lowArticleNumber
+     * @param highArticleNumber
+     * @return a DotTerminatedReader if successful, null otherwise
+     * @throws IOException
+     */
+    public Reader retrieveArticleInfo(int lowArticleNumber,
+                                      int highArticleNumber)
+        throws IOException
+    {
+        return
+            __retrieveArticleInfo(lowArticleNumber + "-" +
+                                             highArticleNumber);
+    }
+
+    /***
+     * Private implementation of XHDR functionality.
+     *
+     * See {@link NNTP#xhdr}
+     * for legal agument formats. Alternatively, read RFC 1036.
+     * <p>
+     * @param header
+     * @param articleRange
+     * @return Returns a DotTerminatedMessageReader if successful, null
+     *         otherwise
+     * @exception IOException
+     */
+    private Reader __retrieveHeader(String header, String articleRange)
+        throws IOException
+    {
+        if (!NNTPReply.isPositiveCompletion(xhdr(header, articleRange)))
+            return null;
+
+        return new DotTerminatedMessageReader(_reader_);
+    }
+
+    /**
+     * Return an article header for a specified post.
+     * <p>
+     * @param header the header to retrieve
+     * @param articleNumber the article to retrieve the header for
+     * @return a DotTerminatedReader if successful, null otherwise
+     * @throws IOException
+     */
+    public Reader retrieveHeader(String header, int articleNumber)
+        throws IOException
+    {
+        return __retrieveHeader(header, Integer.toString(articleNumber));
+    }
+
+    /**
+     * Return an article header for all articles between lowArticleNumber
+     * and highArticleNumber, inclusively.
+     * <p>
+     * @param header
+     * @param lowArticleNumber
+     * @param highArticleNumber
+     * @return a DotTerminatedReader if successful, null otherwise
+     * @throws IOException
+     */
+    public Reader retrieveHeader(String header, int lowArticleNumber,
+                                 int highArticleNumber)
+        throws IOException
+    {
+        return
+            __retrieveHeader(header,lowArticleNumber + "-" + highArticleNumber);
+    }
+}
+
+
+/* Emacs configuration
+ * Local variables:        **
+ * mode:             java  **
+ * c-basic-offset:   4     **
+ * indent-tabs-mode: nil   **
+ * End:                    **
+ */
diff --git a/org/apache/commons/net/nntp/NNTPCommand.java b/org/apache/commons/net/nntp/NNTPCommand.java
new file mode 100644
index 0000000..09f4015
--- /dev/null
+++ b/org/apache/commons/net/nntp/NNTPCommand.java
@@ -0,0 +1,83 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+/***
+ * NNTPCommand stores a set of constants for NNTP command codes.  To interpret
+ * the meaning of the codes, familiarity with RFC 977 is assumed.
+ * <p>
+ * @author Daniel F. Savarese
+ * @author Rory Winston
+ * @author Ted Wise
+ ***/
+
+public final class NNTPCommand
+{
+
+    public static final int ARTICLE   = 0;
+    public static final int BODY      = 1;
+    public static final int GROUP     = 2;
+    public static final int HEAD      = 3;
+    public static final int HELP      = 4;
+    public static final int IHAVE     = 5;
+    public static final int LAST      = 6;
+    public static final int LIST      = 7;
+    public static final int NEWGROUPS = 8;
+    public static final int NEWNEWS   = 9;
+    public static final int NEXT      = 10;
+    public static final int POST      = 11;
+    public static final int QUIT      = 12;
+    public static final int SLAVE     = 13;
+    public static final int STAT      = 14;
+    public static final int AUTHINFO  = 15;
+    public static final int XOVER     = 16;
+    public static final int XHDR      = 17;
+
+    // Cannot be instantiated
+    private NNTPCommand()
+    {}
+
+    static final String[] _commands = {
+        "ARTICLE", "BODY", "GROUP", "HEAD", "HELP", "IHAVE", "LAST", "LIST",
+        "NEWGROUPS", "NEWNEWS", "NEXT", "POST", "QUIT", "SLAVE", "STAT",
+        "AUTHINFO", "XOVER", "XHDR"
+    };
+
+
+    /***
+     * Retrieve the NNTP protocol command string corresponding to a specified
+     * command code.
+     * <p>
+     * @param command The command code.
+     * @return The NNTP protcol command string corresponding to a specified
+     *         command code.
+     ***/
+    public static final String getCommand(int command)
+    {
+        return _commands[command];
+    }
+
+}
+
+/* Emacs configuration
+ * Local variables:        **
+ * mode:             java  **
+ * c-basic-offset:   4     **
+ * indent-tabs-mode: nil   **
+ * End:                    **
+ */
diff --git a/org/apache/commons/net/nntp/NNTPConnectionClosedException.java b/org/apache/commons/net/nntp/NNTPConnectionClosedException.java
new file mode 100644
index 0000000..948ed12
--- /dev/null
+++ b/org/apache/commons/net/nntp/NNTPConnectionClosedException.java
@@ -0,0 +1,56 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+import java.io.IOException;
+
+/***
+ * NNTPConnectionClosedException is used to indicate the premature or
+ * unexpected closing of an NNTP connection resulting from a
+ * {@link org.apache.commons.net.nntp.NNTPReply#SERVICE_DISCONTINUED NNTPReply.SERVICE_DISCONTINUED }
+ *  response (NNTP reply code 400) to a
+ * failed NNTP command.  This exception is derived from IOException and
+ * therefore may be caught either as an IOException or specifically as an
+ * NNTPConnectionClosedException.
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ * @see NNTP
+ * @see NNTPClient
+ ***/
+
+public final class NNTPConnectionClosedException extends IOException
+{
+
+    /*** Constructs a NNTPConnectionClosedException with no message ***/
+    public NNTPConnectionClosedException()
+    {
+        super();
+    }
+
+    /***
+     * Constructs a NNTPConnectionClosedException with a specified message.
+     * <p>
+     * @param message  The message explaining the reason for the exception.
+     ***/
+    public NNTPConnectionClosedException(String message)
+    {
+        super(message);
+    }
+
+}
diff --git a/org/apache/commons/net/nntp/NNTPReply.java b/org/apache/commons/net/nntp/NNTPReply.java
new file mode 100644
index 0000000..f7d0fbd
--- /dev/null
+++ b/org/apache/commons/net/nntp/NNTPReply.java
@@ -0,0 +1,209 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+/***
+ * NNTPReply stores a set of constants for NNTP reply codes.  To interpret
+ * the meaning of the codes, familiarity with RFC 977 is assumed.
+ * The mnemonic constant names are transcriptions from the code descriptions
+ * of RFC 977.  For those who think in terms of the actual reply code values,
+ * a set of CODE_NUM constants are provided where NUM is the numerical value
+ * of the code.
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ ***/
+
+public final class NNTPReply
+{
+
+    public static final int CODE_100 = 100;
+    public static final int CODE_199 = 199;
+    public static final int CODE_200 = 200;
+    public static final int CODE_201 = 201;
+    public static final int CODE_202 = 202;
+    public static final int CODE_205 = 205;
+    public static final int CODE_211 = 211;
+    public static final int CODE_215 = 215;
+    public static final int CODE_220 = 220;
+    public static final int CODE_221 = 221;
+    public static final int CODE_222 = 222;
+    public static final int CODE_223 = 223;
+    public static final int CODE_230 = 230;
+    public static final int CODE_231 = 231;
+    public static final int CODE_235 = 235;
+    public static final int CODE_240 = 240;
+    public static final int CODE_281 = 281;
+    public static final int CODE_335 = 335;
+    public static final int CODE_340 = 340;
+    public static final int CODE_381 = 381;
+    public static final int CODE_400 = 400;
+    public static final int CODE_408 = 408;
+    public static final int CODE_411 = 411;
+    public static final int CODE_412 = 412;
+    public static final int CODE_420 = 420;
+    public static final int CODE_421 = 421;
+    public static final int CODE_422 = 422;
+    public static final int CODE_423 = 423;
+    public static final int CODE_430 = 430;
+    public static final int CODE_435 = 435;
+    public static final int CODE_436 = 436;
+    public static final int CODE_437 = 437;
+    public static final int CODE_440 = 440;
+    public static final int CODE_441 = 441;
+    public static final int CODE_482 = 482;
+    public static final int CODE_500 = 500;
+    public static final int CODE_501 = 501;
+    public static final int CODE_502 = 502;
+    public static final int CODE_503 = 503;
+
+    public static final int HELP_TEXT_FOLLOWS                = CODE_100;
+    public static final int DEBUG_OUTPUT                     = CODE_199;
+    public static final int SERVER_READY_POSTING_ALLOWED     = CODE_200;
+    public static final int SERVER_READY_POSTING_NOT_ALLOWED = CODE_201;
+    public static final int SLAVE_STATUS_NOTED               = CODE_202;
+    public static final int CLOSING_CONNECTION               = CODE_205;
+    public static final int GROUP_SELECTED                   = CODE_211;
+    public static final int ARTICLE_RETRIEVED_HEAD_AND_BODY_FOLLOW = CODE_220;
+    public static final int ARTICLE_RETRIEVED_HEAD_FOLLOWS = CODE_221;
+    public static final int ARTICLE_RETRIEVED_BODY_FOLLOWS = CODE_222;
+    public static final int
+      ARTICLE_RETRIEVED_REQUEST_TEXT_SEPARATELY = CODE_223;
+    public static final int ARTICLE_LIST_BY_MESSAGE_ID_FOLLOWS = CODE_230;
+    public static final int NEW_NEWSGROUP_LIST_FOLLOWS         = CODE_231;
+    public static final int ARTICLE_TRANSFERRED_OK             = CODE_235;
+    public static final int ARTICLE_POSTED_OK                  = CODE_240;
+    public static final int AUTHENTICATION_ACCEPTED            = CODE_281;
+    public static final int SEND_ARTICLE_TO_TRANSFER           = CODE_335;
+    public static final int SEND_ARTICLE_TO_POST               = CODE_340;
+    public static final int MORE_AUTH_INFO_REQUIRED            = CODE_381;
+    public static final int SERVICE_DISCONTINUED               = CODE_400;
+    public static final int NO_SUCH_NEWSGROUP                  = CODE_411;
+    public static final int AUTHENTICATION_REQUIRED            = CODE_408;
+    public static final int NO_NEWSGROUP_SELECTED              = CODE_412;
+    public static final int NO_CURRENT_ARTICLE_SELECTED        = CODE_420;
+    public static final int NO_NEXT_ARTICLE                    = CODE_421;
+    public static final int NO_PREVIOUS_ARTICLE                = CODE_422;
+    public static final int NO_SUCH_ARTICLE_NUMBER             = CODE_423;
+    public static final int NO_SUCH_ARTICLE_FOUND              = CODE_430;
+    public static final int ARTICLE_NOT_WANTED                 = CODE_435;
+    public static final int TRANSFER_FAILED                    = CODE_436;
+    public static final int ARTICLE_REJECTED                   = CODE_437;
+    public static final int POSTING_NOT_ALLOWED                = CODE_440;
+    public static final int POSTING_FAILED                     = CODE_441;
+    public static final int AUTHENTICATION_REJECTED            = CODE_482;
+    public static final int COMMAND_NOT_RECOGNIZED             = CODE_500;
+    public static final int COMMAND_SYNTAX_ERROR               = CODE_501;
+    public static final int PERMISSION_DENIED                  = CODE_502;
+    public static final int PROGRAM_FAULT                      = CODE_503;
+
+    // Cannot be instantiated
+
+    private NNTPReply()
+    {}
+
+    /***
+     * Determine if a reply code is an informational response.  All
+     * codes beginning with a 1 are positive informational responses.
+     * Informational responses are used to provide human readable
+     * information such as help text.
+     * <p>
+     * @param reply  The reply code to test.
+     * @return True if a reply code is an informational response, false
+     *         if not.
+     ***/
+    public static boolean isInformational(int reply)
+    {
+        return (reply >= 100 && reply < 200);
+    }
+
+    /***
+     * Determine if a reply code is a positive completion response.  All
+     * codes beginning with a 2 are positive completion responses.
+     * The NNTP server will send a positive completion response on the final
+     * successful completion of a command.
+     * <p>
+     * @param reply  The reply code to test.
+     * @return True if a reply code is a postive completion response, false
+     *         if not.
+     ***/
+    public static boolean isPositiveCompletion(int reply)
+    {
+        return (reply >= 200 && reply < 300);
+    }
+
+    /***
+     * Determine if a reply code is a positive intermediate response.  All
+     * codes beginning with a 3 are positive intermediate responses.
+     * The NNTP server will send a positive intermediate response on the
+     * successful completion of one part of a multi-part command or
+     * sequence of commands.  For example, after a successful POST command,
+     * a positive intermediate response will be sent to indicate that the
+     * server is ready to receive the article to be posted.
+     * <p>
+     * @param reply  The reply code to test.
+     * @return True if a reply code is a postive intermediate response, false
+     *         if not.
+     ***/
+    public static boolean isPositiveIntermediate(int reply)
+    {
+        return (reply >= 300 && reply < 400);
+    }
+
+    /***
+     * Determine if a reply code is a negative transient response.  All
+     * codes beginning with a 4 are negative transient responses.
+     * The NNTP server will send a negative transient response on the
+     * failure of a correctly formatted command that could not be performed
+     * for some reason.  For example, retrieving an article that does not
+     * exist will result in a negative transient response.
+     * <p>
+     * @param reply  The reply code to test.
+     * @return True if a reply code is a negative transient response, false
+     *         if not.
+     ***/
+    public static boolean isNegativeTransient(int reply)
+    {
+        return (reply >= 400 && reply < 500);
+    }
+
+    /***
+     * Determine if a reply code is a negative permanent response.  All
+     * codes beginning with a 5 are negative permanent responses.
+     * The NNTP server will send a negative permanent response when
+     * it does not implement a command, a command is incorrectly formatted,
+     * or a serious program error occurs.
+     * <p>
+     * @param reply  The reply code to test.
+     * @return True if a reply code is a negative permanent response, false
+     *         if not.
+     ***/
+    public static boolean isNegativePermanent(int reply)
+    {
+        return (reply >= 500 && reply < 600);
+    }
+
+}
+
+/* Emacs configuration
+ * Local variables:        **
+ * mode:             java  **
+ * c-basic-offset:   4     **
+ * indent-tabs-mode: nil   **
+ * End:                    **
+ */
diff --git a/org/apache/commons/net/nntp/NewGroupsOrNewsQuery.java b/org/apache/commons/net/nntp/NewGroupsOrNewsQuery.java
new file mode 100644
index 0000000..a0d9aeb
--- /dev/null
+++ b/org/apache/commons/net/nntp/NewGroupsOrNewsQuery.java
@@ -0,0 +1,283 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+import java.util.Calendar;
+
+/***
+ * The NewGroupsOrNewsQuery class.  This is used to issue NNTP NEWGROUPS and
+ * NEWNEWS queries, implemented by
+ * {@link org.apache.commons.net.nntp.NNTPClient#listNewNewsgroups listNewNewsGroups }
+ *  and
+ * {@link org.apache.commons.net.nntp.NNTPClient#listNewNews listNewNews }
+ *  respectively.  It prevents you from having to format
+ * date, time, distribution, and newgroup arguments.
+ * <p>
+ * You might use the class as follows:
+ * <pre>
+ * query = new NewsGroupsOrNewsQuery(new GregorianCalendar(97, 11, 15), false);
+ * query.addDistribution("comp");
+ * NewsgroupInfo[] newsgroups = client.listNewgroups(query);
+ * </pre>
+ * This will retrieve the list of newsgroups starting with the comp.
+ * distribution prefix created since midnight 11/15/97.
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ * @see NNTPClient
+ ***/
+
+public final class NewGroupsOrNewsQuery
+{
+    private String __date, __time;
+    private StringBuffer __distributions;
+    private StringBuffer __newsgroups;
+    private boolean __isGMT;
+
+
+    /***
+     * Creates a new query using the given time as a reference point.
+     * <p>
+     * @param date  The date since which new groups or news have arrived.
+     * @param gmt   True if the date should be considered as GMT, false if not.
+     ***/
+    public NewGroupsOrNewsQuery(Calendar date, boolean gmt)
+    {
+        int num;
+        String str;
+        StringBuffer buffer;
+
+        __distributions = null;
+        __newsgroups = null;
+        __isGMT = gmt;
+
+        buffer = new StringBuffer();
+
+        // Get year
+        num = date.get(Calendar.YEAR);
+        str = Integer.toString(num);
+        num = str.length();
+
+        if (num >= 2)
+            buffer.append(str.substring(num - 2));
+        else
+            buffer.append("00");
+
+        // Get month
+        num = date.get(Calendar.MONTH) + 1;
+        str = Integer.toString(num);
+        num = str.length();
+
+        if (num == 1)
+        {
+            buffer.append('0');
+            buffer.append(str);
+        }
+        else if (num == 2)
+            buffer.append(str);
+        else
+            buffer.append("01");
+
+        // Get day
+        num = date.get(Calendar.DAY_OF_MONTH);
+        str = Integer.toString(num);
+        num = str.length();
+
+        if (num == 1)
+        {
+            buffer.append('0');
+            buffer.append(str);
+        }
+        else if (num == 2)
+            buffer.append(str);
+        else
+            buffer.append("01");
+
+        __date = buffer.toString();
+
+        buffer.setLength(0);
+
+        // Get hour
+        num = date.get(Calendar.HOUR_OF_DAY);
+        str = Integer.toString(num);
+        num = str.length();
+
+        if (num == 1)
+        {
+            buffer.append('0');
+            buffer.append(str);
+        }
+        else if (num == 2)
+            buffer.append(str);
+        else
+            buffer.append("00");
+
+        // Get minutes
+        num = date.get(Calendar.MINUTE);
+        str = Integer.toString(num);
+        num = str.length();
+
+        if (num == 1)
+        {
+            buffer.append('0');
+            buffer.append(str);
+        }
+        else if (num == 2)
+            buffer.append(str);
+        else
+            buffer.append("00");
+
+
+        // Get seconds
+        num = date.get(Calendar.SECOND);
+        str = Integer.toString(num);
+        num = str.length();
+
+        if (num == 1)
+        {
+            buffer.append('0');
+            buffer.append(str);
+        }
+        else if (num == 2)
+            buffer.append(str);
+        else
+            buffer.append("00");
+
+        __time = buffer.toString();
+    }
+
+
+    /***
+     * Add a newsgroup to the list of newsgroups being queried.  Newsgroups
+     * added this way are only meaningful to the NEWNEWS command.  Newsgroup
+     * names may include the <code> * </code> wildcard, as in
+     * <code>comp.lang.* </code> or <code> comp.lang.java.* </code>.  Adding
+     * at least one newsgroup is mandatory for the NEWNEWS command.
+     * <p>
+     * @param newsgroup  The newsgroup to add to the list of groups to be
+     *                   checked for new news.
+     ***/
+    public void addNewsgroup(String newsgroup)
+    {
+        if (__newsgroups != null)
+            __newsgroups.append(',');
+        else
+            __newsgroups = new StringBuffer();
+        __newsgroups.append(newsgroup);
+    }
+
+
+    /***
+     * Add a newsgroup to the list of newsgroups being queried, but indicate
+     * that group should not be checked for new news.  Newsgroups
+     * added this way are only meaningful to the NEWNEWS command.
+     * Newsgroup names may include the <code> * </code> wildcard, as in
+     * <code>comp.lang.* </code> or <code> comp.lang.java.* </code>.
+     * <p>
+     * The following would create a query that searched for new news in
+     * all comp.lang.java newsgroups except for comp.lang.java.advocacy.
+     * <pre>
+     * query.addNewsgroup("comp.lang.java.*");
+     * query.omitNewsgroup("comp.lang.java.advocacy");
+     * </pre>
+     * <p>
+     * @param newsgroup  The newsgroup to add to the list of groups to be
+     *                   checked for new news, but which should be omitted from
+     *                   the search for new news..
+     ***/
+    public void omitNewsgroup(String newsgroup)
+    {
+        addNewsgroup("!" + newsgroup);
+    }
+
+
+    /***
+     * Add a distribution group to the query.  The distribution part of a
+     * newsgroup is the segment of the name preceding the first dot (e.g.,
+     * comp, alt, rec).  Only those newsgroups matching one of the
+     * distributions or, in the case of NEWNEWS, an article in a newsgroup
+     * matching one of the distributions, will be reported as a query result.
+     * Adding distributions is purely optional.
+     * <p>
+     * @param distribution A distribution to add to the query.
+     ***/
+    public void addDistribution(String distribution)
+    {
+        if (__distributions != null)
+            __distributions.append(',');
+        else
+            __distributions = new StringBuffer();
+        __distributions.append(distribution);
+    }
+
+    /***
+     * Return the NNTP query formatted date (year, month, day in the form
+     * YYMMDD.
+     * <p>
+     * @return The NNTP query formatted date.
+     ***/
+    public String getDate()
+    {
+        return __date;
+    }
+
+    /***
+     * Return the NNTP query formatted time (hour, minutes, seconds in the form
+     * HHMMSS.
+     * <p>
+     * @return The NNTP query formatted time.
+     ***/
+    public String getTime()
+    {
+        return __time;
+    }
+
+    /***
+     * Return whether or not the query date should be treated as GMT.
+     * <p>
+     * @return True if the query date is to be treated as GMT, false if not.
+     ***/
+    public boolean isGMT()
+    {
+        return __isGMT;
+    }
+
+    /***
+     * Return the comma separated list of distributions.  This may be null
+     * if there are no distributions.
+     * <p>
+     * @return The list of distributions, which may be null if no distributions
+     *         have been specified.
+     ***/
+    public String getDistributions()
+    {
+        return (__distributions == null ? null : __distributions.toString());
+    }
+
+    /***
+     * Return the comma separated list of newsgroups.  This may be null
+     * if there are no newsgroups
+     * <p>
+     * @return The list of newsgroups, which may be null if no newsgroups
+     *         have been specified.
+     ***/
+    public String getNewsgroups()
+    {
+        return (__newsgroups == null ? null : __newsgroups.toString());
+    }
+}
diff --git a/org/apache/commons/net/nntp/NewsgroupInfo.java b/org/apache/commons/net/nntp/NewsgroupInfo.java
new file mode 100644
index 0000000..aa48d16
--- /dev/null
+++ b/org/apache/commons/net/nntp/NewsgroupInfo.java
@@ -0,0 +1,155 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+/***
+ * NewsgroupInfo stores information pertaining to a newsgroup returned by
+ * the NNTP GROUP, LIST, and NEWGROUPS commands, implemented by
+ * {@link org.apache.commons.net.nntp.NNTPClient#selectNewsgroup selectNewsgroup }
+ * ,
+ * {@link org.apache.commons.net.nntp.NNTPClient#listNewsgroups listNewsgroups }
+ * , and
+ * {@link org.apache.commons.net.nntp.NNTPClient#listNewNewsgroups listNewNewsgroups }
+ *  respectively.
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ * @see NNTPClient
+ ***/
+
+public final class NewsgroupInfo
+{
+    /***
+     * A constant indicating that the posting permission of a newsgroup is
+     * unknown.  For example, the NNTP GROUP command does not return posting
+     * information, so NewsgroupInfo instances obtained from that command
+     * willhave an UNKNOWN_POSTING_PERMISSION.
+     ***/
+    public static final int UNKNOWN_POSTING_PERMISSION = 0;
+
+    /*** A constant indicating that a newsgroup is moderated. ***/
+    public static final int MODERATED_POSTING_PERMISSION = 1;
+
+    /*** A constant indicating that a newsgroup is public and unmoderated. ***/
+    public static final int PERMITTED_POSTING_PERMISSION = 2;
+
+    /***
+     * A constant indicating that a newsgroup is closed for general posting.
+     ***/
+    public static final int PROHIBITED_POSTING_PERMISSION = 3;
+
+    private String __newsgroup;
+    private int __estimatedArticleCount;
+    private int __firstArticle, __lastArticle;
+    private int __postingPermission;
+
+    void _setNewsgroup(String newsgroup)
+    {
+        __newsgroup = newsgroup;
+    }
+
+    void _setArticleCount(int count)
+    {
+        __estimatedArticleCount = count;
+    }
+
+    void _setFirstArticle(int first)
+    {
+        __firstArticle = first;
+    }
+
+    void _setLastArticle(int last)
+    {
+        __lastArticle = last;
+    }
+
+    void _setPostingPermission(int permission)
+    {
+        __postingPermission = permission;
+    }
+
+    /***
+     * Get the newsgroup name.
+     * <p>
+     * @return The name of the newsgroup.
+     ***/
+    public String getNewsgroup()
+    {
+        return __newsgroup;
+    }
+
+    /***
+     * Get the estimated number of articles in the newsgroup.  The
+     * accuracy of this value will depend on the server implementation.
+     * <p>
+     * @return The estimated number of articles in the newsgroup.
+     ***/
+    public int getArticleCount()
+    {
+        return __estimatedArticleCount;
+    }
+
+    /***
+     * Get the number of the first article in the newsgroup.
+     * <p>
+     * @return The number of the first article in the newsgroup.
+     ***/
+    public int getFirstArticle()
+    {
+        return __firstArticle;
+    }
+
+    /***
+     * Get the number of the last article in the newsgroup.
+     * <p>
+     * @return The number of the last article in the newsgroup.
+     ***/
+    public int getLastArticle()
+    {
+        return __lastArticle;
+    }
+
+    /***
+     * Get the posting permission of the newsgroup.  This will be one of
+     * the <code> POSTING_PERMISSION </code> constants.
+     * <p>
+     * @return The posting permission status of the newsgroup.
+     ***/
+    public int getPostingPermission()
+    {
+        return __postingPermission;
+    }
+
+    /*
+    public String toString() {
+      StringBuffer buffer = new StringBuffer();
+      buffer.append(__newsgroup);
+      buffer.append(' ');
+      buffer.append(__lastArticle);
+      buffer.append(' ');
+      buffer.append(__firstArticle);
+      buffer.append(' ');
+      switch(__postingPermission) {
+        case 1: buffer.append('m'); break;
+        case 2: buffer.append('y'); break;
+        case 3: buffer.append('n'); break;
+      }
+      return buffer.toString();
+}
+    */
+}
diff --git a/org/apache/commons/net/nntp/SimpleNNTPHeader.java b/org/apache/commons/net/nntp/SimpleNNTPHeader.java
new file mode 100644
index 0000000..d18a8cf
--- /dev/null
+++ b/org/apache/commons/net/nntp/SimpleNNTPHeader.java
@@ -0,0 +1,164 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp;
+
+/***
+ * This class is used to construct the bare minimum
+ * acceptable header for most news readers.  To construct more
+ * complicated headers you should refer to RFC 822.  When the
+ * Java Mail API is finalized, you will be
+ * able to use it to compose fully compliant Internet text messages.
+ * <p>
+ * The main purpose of the class is to faciliatate the article posting
+ * process, by relieving the programmer from having to explicitly format
+ * an article header.  For example:
+ * <pre>
+ * writer = client.postArticle();
+ * if(writer == null) // failure
+ *   return false;
+ * header = new SimpleNNTPHeader("foobar@foo.com", "Just testing");
+ * header.addNewsgroup("alt.test");
+ * header.addHeaderField("Organization", "Foobar, Inc.");
+ * writer.write(header.toString());
+ * writer.write("This is just a test");
+ * writer.close();
+ * if(!client.completePendingCommand()) // failure
+ *   return false;
+ * </pre>
+ * <p>
+ * <p>
+ * @author Daniel F. Savarese
+ * @see NNTPClient
+ ***/
+
+public class SimpleNNTPHeader
+{
+    private String __subject, __from;
+    private StringBuilder __newsgroups;
+    private StringBuilder __headerFields;
+    private int __newsgroupCount;
+
+    /***
+     * Creates a new SimpleNNTPHeader instance initialized with the given
+     * from and subject header field values.
+     * <p>
+     * @param from  The value of the <code>From:</code> header field.  This
+     *              should be the article poster's email address.
+     * @param subject  The value of the <code>Subject:</code> header field.
+     *              This should be the subject of the article.
+     ***/
+    public SimpleNNTPHeader(String from, String subject)
+    {
+        __from = from;
+        __subject = subject;
+        __newsgroups = new StringBuilder();
+        __headerFields = new StringBuilder();
+        __newsgroupCount = 0;
+    }
+
+    /***
+     * Adds a newsgroup to the article <code>Newsgroups:</code> field.
+     * <p>
+     * @param newsgroup  The newsgroup to add to the article's newsgroup
+     *                   distribution list.
+     ***/
+    public void addNewsgroup(String newsgroup)
+    {
+        if (__newsgroupCount++ > 0)
+            __newsgroups.append(',');
+        __newsgroups.append(newsgroup);
+    }
+
+    /***
+     * Adds an arbitrary header field with the given value to the article
+     * header.  These headers will be written after the From, Newsgroups,
+     * and Subject fields when the SimpleNNTPHeader is convertered to a string.
+     * An example use would be:
+     * <pre>
+     * header.addHeaderField("Organization", "Foobar, Inc.");
+     * </pre>
+     * <p>
+     * @param headerField  The header field to add, not including the colon.
+     * @param value  The value of the added header field.
+     ***/
+    public void addHeaderField(String headerField, String value)
+    {
+        __headerFields.append(headerField);
+        __headerFields.append(": ");
+        __headerFields.append(value);
+        __headerFields.append('\n');
+    }
+
+
+    /***
+     * Returns the address used in the <code> From: </code> header field.
+     * <p>
+     * @return The from address.
+     ***/
+    public String getFromAddress()
+    {
+        return __from;
+    }
+
+    /***
+     * Returns the subject used in the <code> Subject: </code> header field.
+     * <p>
+     * @return The subject.
+     ***/
+    public String getSubject()
+    {
+        return __subject;
+    }
+
+    /***
+     * Returns the contents of the <code> Newsgroups: </code> header field.
+     * <p>
+     * @return The comma-separated list of newsgroups to which the article
+     *         is being posted.
+     ***/
+    public String getNewsgroups()
+    {
+        return __newsgroups.toString();
+    }
+
+    /***
+     * Converts the SimpleNNTPHeader to a properly formatted header in
+     * the form of a String, including the blank line used to separate
+     * the header from the article body.
+     * <p>
+     * @return The article header in the form of a String.
+     ***/
+    @Override
+    public String toString()
+    {
+        StringBuffer header = new StringBuffer();
+
+        header.append("From: ");
+        header.append(__from);
+        header.append("\nNewsgroups: ");
+        header.append(__newsgroups.toString());
+        header.append("\nSubject: ");
+        header.append(__subject);
+        header.append('\n');
+        if (__headerFields.length() > 0)
+            header.append(__headerFields.toString());
+        header.append('\n');
+
+        return header.toString();
+    }
+}
diff --git a/org/apache/commons/net/nntp/Threadable.java b/org/apache/commons/net/nntp/Threadable.java
new file mode 100644
index 0000000..518a9a4
--- /dev/null
+++ b/org/apache/commons/net/nntp/Threadable.java
@@ -0,0 +1,34 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.net.nntp; 
+
+/**
+ * A placeholder interface for threadable message objects
+ * Author: Rory Winston <rwinston@checkfree.com>
+ *
+ */
+public interface Threadable {
+    public boolean isDummy();
+    public String messageThreadId();
+    public String[] messageThreadReferences();
+    public String simplifiedSubject();
+    public boolean subjectIsReply();
+    public void setChild(Threadable child); 
+    public void setNext(Threadable next);
+    public Threadable makeDummy();
+}
diff --git a/org/apache/commons/net/nntp/Threader.java b/org/apache/commons/net/nntp/Threader.java
new file mode 100644
index 0000000..d702c67
--- /dev/null
+++ b/org/apache/commons/net/nntp/Threader.java
@@ -0,0 +1,481 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+package org.apache.commons.net.nntp;
+
+/**
+ * This is an implementation of a message threading algorithm, as originally devised by Zamie Zawinski.
+ * See <a href="http://www.jwz.org/doc/threading.html">http://www.jwz.org/doc/threading.html</a> for details.
+ * For his Java implementation, see <a href="http://lxr.mozilla.org/mozilla/source/grendel/sources/grendel/view/Threader.java">http://lxr.mozilla.org/mozilla/source/grendel/sources/grendel/view/Threader.java</a>
+ *  
+ * @author rwinston <rwinston@checkfree.com>
+ *
+ */
+
+import java.util.HashMap;
+import java.util.Iterator;
+
+public class Threader {
+    private ThreadContainer root;
+    private HashMap<String,ThreadContainer> idTable;
+    private int bogusIdCount = 0;
+
+    /**
+     * The main threader entry point - The client passes in an array of Threadable objects, and 
+     * the Threader constructs a connected 'graph' of messages
+     * @param messages
+     * @return
+     */
+    public Threadable thread(Threadable[] messages) {
+        if (messages == null)
+            return null;
+
+        idTable = new HashMap<String,ThreadContainer>();
+
+        // walk through each Threadable element
+        for (int i = 0; i < messages.length; ++i) {
+            if (!messages[i].isDummy())
+                buildContainer(messages[i]);
+        }
+
+        root = findRootSet();
+        idTable.clear();
+        idTable = null;
+
+        pruneEmptyContainers(root);
+
+        root.reverseChildren();
+        gatherSubjects();
+
+        if (root.next != null)
+            throw new RuntimeException("root node has a next:" + root);
+
+        for (ThreadContainer r = root.child; r != null; r = r.next) {
+            if (r.threadable == null)
+                r.threadable = r.child.threadable.makeDummy();
+        }
+
+        Threadable result = (root.child == null ? null : root.child.threadable);
+        root.flush();
+        root = null;
+
+        return result;
+    }
+
+    /**
+     * 
+     * @param threadable
+     */
+    private void buildContainer(Threadable threadable) {
+        String id = threadable.messageThreadId();
+        ThreadContainer container = idTable.get(id);
+
+        // A ThreadContainer exists for this id already. This should be a forward reference, but may 
+        // be a duplicate id, in which case we will need to generate a bogus placeholder id
+        if (container != null) {
+            if (container.threadable != null) { // oops! duplicate ids...
+                id = "<Bogus-id:" + (bogusIdCount++) + ">";
+                container = null;
+            } else {
+                // The container just contained a forward reference to this message, so let's
+                // fill in the threadable field of the container with this message
+                container.threadable = threadable;
+            }
+        }
+
+        // No container exists for that message Id. Create one and insert it into the hash table.
+        if (container == null) {
+            container = new ThreadContainer();
+            container.threadable = threadable;
+            idTable.put(id, container);
+        }
+
+        // Iterate through all of the references and create ThreadContainers for any references that
+        // don't have them.
+        ThreadContainer parentRef = null;
+        {
+            String[] references = threadable.messageThreadReferences();
+            for (int i = 0; i < references.length; ++i) {
+                String refString = references[i];
+                ThreadContainer ref = idTable.get(refString);
+
+                // if this id doesnt have a container, create one
+                if (ref == null) {
+                    ref = new ThreadContainer();
+                    idTable.put(refString, ref);
+                }
+
+                // Link references together in the order they appear in the References: header,
+                // IF they dont have a have a parent already &&
+                // IF it will not cause a circular reference
+                if ((parentRef != null)
+                    && (ref.parent == null)
+                    && (parentRef != ref)
+                    && !(parentRef.findChild(ref))) {
+                    // Link ref into the parent's child list
+                    ref.parent = parentRef;
+                    ref.next = parentRef.child;
+                    parentRef.child = ref;
+                }
+                parentRef = ref;
+            }
+        }
+
+        // parentRef is now set to the container of the last element in the references field. make that 
+        // be the parent of this container, unless doing so causes a circular reference
+        if (parentRef != null
+            && (parentRef == container || container.findChild(parentRef)))
+            parentRef = null;
+
+        // if it has a parent already, its because we saw this message in a References: field, and presumed
+        // a parent based on the other entries in that field. Now that we have the actual message, we can
+        // throw away the old parent and use this new one
+        if (container.parent != null) {
+            ThreadContainer rest, prev;
+
+            for (prev = null, rest = container.parent.child;
+                rest != null;
+                prev = rest, rest = rest.next) {
+                if (rest == container)
+                    break;
+            }
+
+            if (rest == null) {
+                throw new RuntimeException(
+                    "Didnt find "
+                        + container
+                        + " in parent"
+                        + container.parent);
+            }
+
+            // Unlink this container from the parent's child list
+            if (prev == null)
+                container.parent.child = container.next;
+            else
+                prev.next = container.next;
+
+            container.next = null;
+            container.parent = null;
+        }
+
+        // If we have a parent, link container into the parents child list
+        if (parentRef != null) {
+            container.parent = parentRef;
+            container.next = parentRef.child;
+            parentRef.child = container;
+        }
+    }
+
+    /**
+     * Find the root set of all existing ThreadContainers
+     * @return root the ThreadContainer representing the root node
+     */
+    private ThreadContainer findRootSet() {
+        ThreadContainer root = new ThreadContainer();
+        Iterator<String> iter = idTable.keySet().iterator();
+
+        while (iter.hasNext()) {
+            Object key = iter.next();
+            ThreadContainer c = idTable.get(key);
+            if (c.parent == null) {
+                if (c.next != null)
+                    throw new RuntimeException(
+                        "c.next is " + c.next.toString());
+                c.next = root.child;
+                root.child = c;
+            }
+        }
+        return root;
+    }
+
+    /**
+     * Delete any empty or dummy ThreadContainers
+     * @param parent
+     */
+    private void pruneEmptyContainers(ThreadContainer parent) {
+        ThreadContainer container, prev, next;
+        for (prev = null, container = parent.child, next = container.next;
+            container != null;
+            prev = container,
+                container = next,
+                next = (container == null ? null : container.next)) {
+
+            // Is it empty and without any children? If so,delete it 
+            if (container.threadable == null && container.child == null) {
+                if (prev == null)
+                    parent.child = container.next;
+                else
+                    prev.next = container.next;
+
+                // Set container to prev so that prev keeps its same value the next time through the loop
+                container = prev;
+            }
+
+            // Else if empty, with kids, and (not at root or only one kid)
+            else if (
+                container.threadable == null
+                    && container.child != null
+                    && (container.parent != null
+                        || container.child.next == null)) {
+                // We have an invalid/expired message with kids. Promote the kids to this level. 
+                ThreadContainer tail;
+                ThreadContainer kids = container.child;
+
+                // Remove this container and replace with 'kids'.
+                if (prev == null)
+                    parent.child = kids;
+                else
+                    prev.next = kids;
+
+                // Make each child's parent be this level's parent -> i.e. promote the children. Make the last child's next point to this container's next
+                // i.e. splice kids into the list in place of container
+                for (tail = kids; tail.next != null; tail = tail.next)
+                    tail.parent = container.parent;
+
+                tail.parent = container.parent;
+                tail.next = container.next;
+
+                // next currently points to the item after the inserted items in the chain - reset that so we process the newly
+                // promoted items next time round
+                next = kids;
+
+                // Set container to prev so that prev keeps its same value the next time through the loop
+                container = prev;
+            } else if (container.child != null) {
+                // A real message , with kids
+                // Iterate over the children
+                pruneEmptyContainers(container);
+            }
+        }
+    }
+
+    /**
+     *  If any two members of the root set have the same subject, merge them. This is to attempt to accomodate messages without References: headers. 
+     */
+    private void gatherSubjects() {
+
+        int count = 0;
+
+        for (ThreadContainer c = root.child; c != null; c = c.next)
+            count++;
+
+        // TODO verify this will avoid rehashing
+        HashMap<String, ThreadContainer> subjectTable = new HashMap<String, ThreadContainer>((int) (count * 1.2), (float) 0.9);
+        count = 0;
+
+        for (ThreadContainer c = root.child; c != null; c = c.next) {
+            Threadable threadable = c.threadable;
+
+            // No threadable? If so, it is a dummy node in the root set.
+            // Only root set members may be dummies, and they alway have at least 2 kids
+            // Take the first kid as representative of the subject
+            if (threadable == null)
+                threadable = c.child.threadable;
+
+            String subj = threadable.simplifiedSubject();
+
+            if (subj == null || subj == "")
+                continue;
+
+            ThreadContainer old = subjectTable.get(subj);
+
+            // Add this container to the table iff:
+            // - There exists no container with this subject
+            // - or this is a dummy container and the old one is not - the dummy one is
+            // more interesting as a root, so put it in the table instead
+            // - The container in the table has a "Re:" version of this subject, and 
+            // this container has a non-"Re:" version of this subject. The non-"Re:" version
+            // is the more interesting of the two.
+            if (old == null
+                || (c.threadable == null && old.threadable != null)
+                || (old.threadable != null
+                    && old.threadable.subjectIsReply()
+                    && c.threadable != null
+                    && !c.threadable.subjectIsReply())) {
+                subjectTable.put(subj, c);
+                count++;
+            }
+        }
+
+        // If the table is empty, we're done
+        if (count == 0)
+            return;
+
+        // subjectTable is now populated with one entry for each subject which occurs in the 
+        // root set. Iterate over the root set, and gather together the difference.
+        ThreadContainer prev, c, rest;
+        for (prev = null, c = root.child, rest = c.next;
+            c != null;
+            prev = c, c = rest, rest = (rest == null ? null : rest.next)) {
+            Threadable threadable = c.threadable;
+
+            // is it a dummy node?
+            if (threadable == null)
+                threadable = c.child.threadable;
+
+            String subj = threadable.simplifiedSubject();
+
+            // Dont thread together all subjectless messages
+            if (subj == null || subj == "")
+                continue;
+
+            ThreadContainer old = subjectTable.get(subj);
+
+            if (old == c) // That's us
+                continue;
+
+            // We have now found another container in the root set with the same subject
+            // Remove the "second" message from the root set
+            if (prev == null)
+                root.child = c.next;
+            else
+                prev.next = c.next;
+            c.next = null;
+
+            if (old.threadable == null && c.threadable == null) {
+                // both dummies - merge them
+                ThreadContainer tail;
+                for (tail = old.child;
+                    tail != null && tail.next != null;
+                    tail = tail.next);
+
+                tail.next = c.child;
+
+                for (tail = c.child; tail != null; tail = tail.next)
+                    tail.parent = old;
+
+                c.child = null;
+            } else if (
+                old.threadable == null
+                    || (c.threadable != null
+                        && c.threadable.subjectIsReply()
+                        && !old.threadable.subjectIsReply())) {
+                // Else if old is empty, or c has "Re:" and old does not  ==> make this message a child of old
+                c.parent = old;
+                c.next = old.child;
+                old.child = c;
+            } else {
+                // else make the old and new messages be children of a new dummy container.
+                // We create a new container object for old.msg and empty the old container
+                ThreadContainer newc = new ThreadContainer();
+                newc.threadable = old.threadable;
+                newc.child = old.child;
+
+                for (ThreadContainer tail = newc.child;
+                    tail != null;
+                    tail = tail.next)
+                    tail.parent = newc;
+
+                old.threadable = null;
+                old.child = null;
+
+                c.parent = old;
+                newc.parent = old;
+
+                // Old is now a dummy- give it 2 kids , c and newc
+                old.child = c;
+                c.next = newc;
+            }
+            // We've done a merge, so keep the same prev
+            c = prev;
+        }
+
+        subjectTable.clear();
+        subjectTable = null;
+
+    }
+}
+
+/**
+ * A placeholder utility class, used for constructing a tree of Threadables
+ * Originall implementation by Jamie Zawinski. 
+ * See the Grendel source for more details <a href="http://lxr.mozilla.org/mozilla/source/grendel/sources/grendel/view/Threader.java#511">here</a>
+ * Threadable objects
+ * @author Rory Winston <rwinston@checkfree.com>
+ */
+class ThreadContainer {
+    Threadable threadable;
+    ThreadContainer parent;
+    ThreadContainer prev;
+    ThreadContainer next;
+    ThreadContainer child;
+
+    /**
+     * 
+     * @param container
+     * @return true if child is under self's tree. Detects circular references
+     */
+    boolean findChild(ThreadContainer target) {
+        if (child == null)
+            return false;
+
+        else if (child == target)
+            return true;
+        else
+            return child.findChild(target);
+    }
+
+    // Copy the ThreadContainer tree structure down into the underlying Threadable objects
+    // (Make the Threadable tree look like the ThreadContainer tree)
+    void flush() {
+        if (parent != null && threadable == null)
+            throw new RuntimeException("no threadable in " + this.toString());
+
+        parent = null;
+
+        if (threadable != null)
+            threadable.setChild(child == null ? null : child.threadable);
+
+        if (child != null) {
+            child.flush();
+            child = null;
+        }
+
+        if (threadable != null)
+            threadable.setNext(next == null ? null : next.threadable);
+
+        if (next != null) {
+            next.flush();
+            next = null;
+        }
+
+        threadable = null;
+    }
+
+    /**
+     * Reverse the entire set of children
+     *
+     */
+    void reverseChildren() {
+        if (child != null) {
+            ThreadContainer kid, prev, rest;
+            for (prev = null, kid = child, rest = kid.next;
+                kid != null;
+                prev = kid,
+                    kid = rest,
+                    rest = (rest == null ? null : rest.next))
+                kid.next = prev;
+
+            child = prev;
+
+            // Do it for the kids 
+            for (kid = child; kid != null; kid = kid.next)
+                kid.reverseChildren();
+        }
+    }
+}
author	Joe Robinson <joe@lc8n.com>	2010-10-27 14:21:09 +0100
committer	Joe Robinson <joe@lc8n.com>	2010-10-27 14:21:09 +0100
commit	063284837c8c366e5502b1b0264b8eb807b61732 (patch)
tree	fff3a1e1e5afaa671485b9d990704658276627ac /org/apache/commons/net/nntp