/* * 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.FilterOutputStream; import java.io.IOException; import java.io.OutputStream; /*** * This class wraps an output stream, replacing all occurrences * of <CR><LF> (carriage return followed by a linefeed), * which is the NETASCII standard for representing a newline, with the * local line separator representation. You would use this class to * implement ASCII file transfers requiring conversion from NETASCII. *

* Because of the translation process, a call to flush() will * not flush the last byte written if that byte was a carriage * return. A call to {@link #close close() }, however, will * flush the carriage return. *

*

* @author Daniel F. Savarese ***/ public final class FromNetASCIIOutputStream extends FilterOutputStream { private boolean __lastWasCR; /*** * Creates a FromNetASCIIOutputStream instance that wraps an existing * OutputStream. *

* @param output The OutputStream to wrap. ***/ public FromNetASCIIOutputStream(OutputStream output) { super(output); __lastWasCR = false; } private void __write(int ch) throws IOException { switch (ch) { case '\r': __lastWasCR = true; // Don't write anything. We need to see if next one is linefeed break; case '\n': if (__lastWasCR) { out.write(FromNetASCIIInputStream._lineSeparatorBytes); __lastWasCR = false; break; } __lastWasCR = false; out.write('\n'); break; default: if (__lastWasCR) { out.write('\r'); __lastWasCR = false; } out.write(ch); break; } } /*** * Writes a byte to the stream. Note that a call to this method * might not actually write a byte to the underlying stream until a * subsequent character is written, from which it can be determined if * a NETASCII line separator was encountered. * This is transparent to the programmer and is only mentioned for * completeness. *

* @param ch The byte to write. * @exception IOException If an error occurs while writing to the underlying * stream. ***/ @Override public synchronized void write(int ch) throws IOException { if (FromNetASCIIInputStream._noConversionRequired) { out.write(ch); return ; } __write(ch); } /*** * Writes a byte array to the stream. *

* @param buffer The byte array to write. * @exception IOException If an error occurs while writing to the underlying * stream. ***/ @Override public synchronized void write(byte buffer[]) throws IOException { write(buffer, 0, buffer.length); } /*** * Writes a number of bytes from a byte array to the stream starting from * a given offset. *

* @param buffer The byte array to write. * @param offset The offset into the array at which to start copying data. * @param length The number of bytes to write. * @exception IOException If an error occurs while writing to the underlying * stream. ***/ @Override public synchronized void write(byte buffer[], int offset, int length) throws IOException { if (FromNetASCIIInputStream._noConversionRequired) { // FilterOutputStream method is very slow. //super.write(buffer, offset, length); out.write(buffer, offset, length); return ; } while (length-- > 0) __write(buffer[offset++]); } /*** * Closes the stream, writing all pending data. *

* @exception IOException If an error occurs while closing the stream. ***/ @Override public synchronized void close() throws IOException { if (FromNetASCIIInputStream._noConversionRequired) { super.close(); return ; } if (__lastWasCR) out.write('\r'); super.close(); } }