/*
 * 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 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.
/***
 * This class wraps an output stream, replacing all singly occurring
 * &lt;LF&gt; (linefeed) characters with &lt;CR&gt;&lt;LF&gt; (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.
Params:
output –  The OutputStream to wrap./***
     * 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.
Params:
ch – The byte to write.
Throws:
IOException – If an error occurs while writing to the underlying
           stream./***
     * 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.
     * @throws 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.
Params:
buffer –  The byte array to write.
Throws:
IOException – If an error occurs while writing to the underlying
           stream./***
     * Writes a byte array to the stream.
     *
     * @param buffer  The byte array to write.
     * @throws 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.
Params:
buffer –  The byte array to write.
offset –  The offset into the array at which to start copying data.
length –  The number of bytes to write.
Throws:
IOException – If an error occurs while writing to the underlying
           stream./***
     * 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.
     * @throws 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++]);
        }
    }

}