summaryrefslogtreecommitdiff
path: root/app/src/main/java/org/apache/commons/net/io/Util.java
blob: 4e85a9321d27dd94157b447460c39dc1c336c8f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
/*
 * 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.io;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;

/***
 * The Util class cannot be instantiated and stores short static convenience
 * methods that are often quite useful.
 * <p>
 * <p>
 * @see CopyStreamException
 * @see CopyStreamListener
 * @see CopyStreamAdapter
 * @author Daniel F. Savarese
 ***/

public final class Util
{
    /***
     * The default buffer size used by {@link #copyStream  copyStream }
     * and {@link #copyReader  copyReader }. It's value is 1024.
     ***/
    public static final int DEFAULT_COPY_BUFFER_SIZE = 1024;

    // Cannot be instantiated
    private Util()
    { }


    /***
     * Copies the contents of an InputStream to an OutputStream using a
     * copy buffer of a given size and notifies the provided
     * CopyStreamListener of the progress of the copy operation by calling
     * its bytesTransferred(long, int) method after each write to the
     * destination.  If you wish to notify more than one listener you should
     * use a CopyStreamAdapter as the listener and register the additional
     * listeners with the CopyStreamAdapter.
     * <p>
     * The contents of the InputStream are
     * read until the end of the stream is reached, but neither the
     * source nor the destination are closed.  You must do this yourself
     * outside of the method call.  The number of bytes read/written is
     * returned.
     * <p>
     * @param source  The source InputStream.
     * @param dest    The destination OutputStream.
     * @param bufferSize  The number of bytes to buffer during the copy.
     * @param streamSize  The number of bytes in the stream being copied.
     *          Should be set to CopyStreamEvent.UNKNOWN_STREAM_SIZE if unknown.
     * @param listener  The CopyStreamListener to notify of progress.  If
     *      this parameter is null, notification is not attempted.
     * @param flush Whether to flush the output stream after every
     *        write.  This is necessary for interactive sessions that rely on
     *        buffered streams.  If you don't flush, the data will stay in
     *        the stream buffer.
     * @exception CopyStreamException  If an error occurs while reading from the
     *            source or writing to the destination.  The CopyStreamException
     *            will contain the number of bytes confirmed to have been
     *            transferred before an
     *            IOException occurred, and it will also contain the IOException
     *            that caused the error.  These values can be retrieved with
     *            the CopyStreamException getTotalBytesTransferred() and
     *            getIOException() methods.
     ***/
    public static final long copyStream(InputStream source, OutputStream dest,
                                        int bufferSize, long streamSize,
                                        CopyStreamListener listener,
                                        boolean flush)
    throws CopyStreamException
    {
        int bytes;
        long total;
        byte[] buffer;

        buffer = new byte[bufferSize];
        total = 0;

        try
        {
            while ((bytes = source.read(buffer)) != -1)
            {
                // Technically, some read(byte[]) methods may return 0 and we cannot
                // accept that as an indication of EOF.

                if (bytes == 0)
                {
                    bytes = source.read();
                    if (bytes < 0)
                        break;
                    dest.write(bytes);
                    if(flush)
                      dest.flush();
                    ++total;
                    if (listener != null)
                        listener.bytesTransferred(total, 1, streamSize);
                    continue;
                }

                dest.write(buffer, 0, bytes);
                if(flush)
                  dest.flush();
                total += bytes;
                if (listener != null)
                    listener.bytesTransferred(total, bytes, streamSize);
            }
        }
        catch (IOException e)
        {
            throw new CopyStreamException("IOException caught while copying.",
                                          total, e);
        }

        return total;
    }


    /***
     * Copies the contents of an InputStream to an OutputStream using a
     * copy buffer of a given size and notifies the provided
     * CopyStreamListener of the progress of the copy operation by calling
     * its bytesTransferred(long, int) method after each write to the
     * destination.  If you wish to notify more than one listener you should
     * use a CopyStreamAdapter as the listener and register the additional
     * listeners with the CopyStreamAdapter.
     * <p>
     * The contents of the InputStream are
     * read until the end of the stream is reached, but neither the
     * source nor the destination are closed.  You must do this yourself
     * outside of the method call.  The number of bytes read/written is
     * returned.
     * <p>
     * @param source  The source InputStream.
     * @param dest    The destination OutputStream.
     * @param bufferSize  The number of bytes to buffer during the copy.
     * @param streamSize  The number of bytes in the stream being copied.
     *          Should be set to CopyStreamEvent.UNKNOWN_STREAM_SIZE if unknown.
     * @param listener  The CopyStreamListener to notify of progress.  If
     *      this parameter is null, notification is not attempted.
     * @exception CopyStreamException  If an error occurs while reading from the
     *            source or writing to the destination.  The CopyStreamException
     *            will contain the number of bytes confirmed to have been
     *            transferred before an
     *            IOException occurred, and it will also contain the IOException
     *            that caused the error.  These values can be retrieved with
     *            the CopyStreamException getTotalBytesTransferred() and
     *            getIOException() methods.
     ***/
    public static final long copyStream(InputStream source, OutputStream dest,
                                        int bufferSize, long streamSize,
                                        CopyStreamListener listener)
    throws CopyStreamException
    {
      return copyStream(source, dest, bufferSize, streamSize, listener,
                        true);
    }


    /***
     * Copies the contents of an InputStream to an OutputStream using a
     * copy buffer of a given size.  The contents of the InputStream are
     * read until the end of the stream is reached, but neither the
     * source nor the destination are closed.  You must do this yourself
     * outside of the method call.  The number of bytes read/written is
     * returned.
     * <p>
     * @param source  The source InputStream.
     * @param dest    The destination OutputStream.
     * @return  The number of bytes read/written in the copy operation.
     * @exception CopyStreamException  If an error occurs while reading from the
     *            source or writing to the destination.  The CopyStreamException
     *            will contain the number of bytes confirmed to have been
     *            transferred before an
     *            IOException occurred, and it will also contain the IOException
     *            that caused the error.  These values can be retrieved with
     *            the CopyStreamException getTotalBytesTransferred() and
     *            getIOException() methods.
     ***/
    public static final long copyStream(InputStream source, OutputStream dest,
                                        int bufferSize)
    throws CopyStreamException
    {
        return copyStream(source, dest, bufferSize,
                          CopyStreamEvent.UNKNOWN_STREAM_SIZE, null);
    }


    /***
     * Same as <code> copyStream(source, dest, DEFAULT_COPY_BUFFER_SIZE); </code>
     ***/
    public static final long copyStream(InputStream source, OutputStream dest)
    throws CopyStreamException
    {
        return copyStream(source, dest, DEFAULT_COPY_BUFFER_SIZE);
    }


    /***
     * Copies the contents of a Reader to a Writer using a
     * copy buffer of a given size and notifies the provided
     * CopyStreamListener of the progress of the copy operation by calling
     * its bytesTransferred(long, int) method after each write to the
     * destination.  If you wish to notify more than one listener you should
     * use a CopyStreamAdapter as the listener and register the additional
     * listeners with the CopyStreamAdapter.
     * <p>
     * The contents of the Reader are
     * read until its end is reached, but neither the source nor the
     * destination are closed.  You must do this yourself outside of the
     * method call.  The number of characters read/written is returned.
     * <p>
     * @param source  The source Reader.
     * @param dest    The destination writer.
     * @param bufferSize  The number of characters to buffer during the copy.
     * @param streamSize  The number of characters in the stream being copied.
     *          Should be set to CopyStreamEvent.UNKNOWN_STREAM_SIZE if unknown.
     * @param listener  The CopyStreamListener to notify of progress.  If
     *      this parameter is null, notification is not attempted.
     * @return  The number of characters read/written in the copy operation.
     * @exception CopyStreamException  If an error occurs while reading from the
     *            source or writing to the destination.  The CopyStreamException
     *            will contain the number of bytes confirmed to have been
     *            transferred before an
     *            IOException occurred, and it will also contain the IOException
     *            that caused the error.  These values can be retrieved with
     *            the CopyStreamException getTotalBytesTransferred() and
     *            getIOException() methods.
     ***/
    public static final long copyReader(Reader source, Writer dest,
                                        int bufferSize, long streamSize,
                                        CopyStreamListener listener)
    throws CopyStreamException
    {
        int chars;
        long total;
        char[] buffer;

        buffer = new char[bufferSize];
        total = 0;

        try
        {
            while ((chars = source.read(buffer)) != -1)
            {
                // Technically, some read(char[]) methods may return 0 and we cannot
                // accept that as an indication of EOF.
                if (chars == 0)
                {
                    chars = source.read();
                    if (chars < 0)
                        break;
                    dest.write(chars);
                    dest.flush();
                    ++total;
                    if (listener != null)
                        listener.bytesTransferred(total, chars, streamSize);
                    continue;
                }

                dest.write(buffer, 0, chars);
                dest.flush();
                total += chars;
                if (listener != null)
                    listener.bytesTransferred(total, chars, streamSize);
            }
        }
        catch (IOException e)
        {
            throw new CopyStreamException("IOException caught while copying.",
                                          total, e);
        }

        return total;
    }


    /***
     * Copies the contents of a Reader to a Writer using a
     * copy buffer of a given size.  The contents of the Reader are
     * read until its end is reached, but neither the source nor the
     * destination are closed.  You must do this yourself outside of the
     * method call.  The number of characters read/written is returned.
     * <p>
     * @param source  The source Reader.
     * @param dest    The destination writer.
     * @param bufferSize  The number of characters to buffer during the copy.
     * @return  The number of characters read/written in the copy operation.
     * @exception CopyStreamException  If an error occurs while reading from the
     *            source or writing to the destination.  The CopyStreamException
     *            will contain the number of bytes confirmed to have been
     *            transferred before an
     *            IOException occurred, and it will also contain the IOException
     *            that caused the error.  These values can be retrieved with
     *            the CopyStreamException getTotalBytesTransferred() and
     *            getIOException() methods.
     ***/
    public static final long copyReader(Reader source, Writer dest,
                                        int bufferSize)
    throws CopyStreamException
    {
        return copyReader(source, dest, bufferSize,
                          CopyStreamEvent.UNKNOWN_STREAM_SIZE, null);
    }


    /***
     * Same as <code> copyReader(source, dest, DEFAULT_COPY_BUFFER_SIZE); </code>
     ***/
    public static final long copyReader(Reader source, Writer dest)
    throws CopyStreamException
    {
        return copyReader(source, dest, DEFAULT_COPY_BUFFER_SIZE);
    }

}