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Panda Core is the core module of Panda Framework, it contains commonly used utility classes similar to apache-commons.

There is a newer version: 1.8.0

package panda.net.io;

import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;

/***
 * This class wraps an output stream, replacing all singly occurring <LF> (linefeed)
 * characters with <CR><LF> (carriage return followed by linefeed), which is the
 * NETASCII standard for representing a newline. You would use this class to implement ASCII file
 * transfers requiring conversion to NETASCII.
 ***/

public final class ToNetASCIIOutputStream extends FilterOutputStream {
	private boolean __lastWasCR;

	/***
	 * Creates a ToNetASCIIOutputStream instance that wraps an existing OutputStream.
	 * 
	 * @param output The OutputStream to wrap.
	 ***/
	public ToNetASCIIOutputStream(OutputStream output) {
		super(output);
		__lastWasCR = false;
	}

	/***
	 * Writes a byte to the stream. Note that a call to this method may result in multiple writes to
	 * the underlying input stream in order to convert naked newlines to NETASCII line separators.
	 * 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 {
		switch (ch) {
		case '\r':
			__lastWasCR = true;
			out.write('\r');
			return;
		case '\n':
			if (!__lastWasCR) {
				out.write('\r');
			}
			//$FALL-THROUGH$
		default:
			__lastWasCR = false;
			out.write(ch);
			return;
		}
	}

	/***
	 * 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 {
		while (length-- > 0) {
			write(buffer[offset++]);
		}
	}

}