001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.net.io;
019
020import java.io.FilterOutputStream;
021import java.io.IOException;
022import java.io.OutputStream;
023import java.net.Socket;
024
025/**
026 * This class wraps an output stream, storing a reference to its originating socket. When the stream is closed, it will also close the socket immediately
027 * afterward. This class is useful for situations where you are dealing with a stream originating from a socket, but do not have a reference to the socket, and
028 * want to make sure it closes when the stream closes.
029 *
030 *
031 * @see SocketInputStream
032 */
033
034public class SocketOutputStream extends FilterOutputStream {
035    private final Socket socket;
036
037    /**
038     * Creates a SocketOutputStream instance wrapping an output stream and storing a reference to a socket that should be closed on closing the stream.
039     *
040     * @param socket The socket to close on closing the stream.
041     * @param stream The input stream to wrap.
042     */
043    public SocketOutputStream(final Socket socket, final OutputStream stream) {
044        super(stream);
045        this.socket = socket;
046    }
047
048    /**
049     * Closes the stream and immediately afterward closes the referenced socket.
050     *
051     * @throws IOException If there is an error in closing the stream or socket.
052     */
053    @Override
054    public void close() throws IOException {
055        super.close();
056        socket.close();
057    }
058
059    /**
060     * Writes a number of bytes from a byte array to the stream starting from a given offset. This method bypasses the equivalent method in FilterOutputStream
061     * because the FilterOutputStream implementation is very inefficient.
062     *
063     * @param buffer The byte array to write.
064     * @param offset The offset into the array at which to start copying data.
065     * @param length The number of bytes to write.
066     * @throws IOException If an error occurs while writing to the underlying stream.
067     */
068    @Override
069    public void write(final byte buffer[], final int offset, final int length) throws IOException {
070        out.write(buffer, offset, length);
071    }
072}