001/*
002 *   Licensed to the Apache Software Foundation (ASF) under one
003 *   or more contributor license agreements.  See the NOTICE file
004 *   distributed with this work for additional information
005 *   regarding copyright ownership.  The ASF licenses this file
006 *   to you under the Apache License, Version 2.0 (the
007 *   "License"); you may not use this file except in compliance
008 *   with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *   Unless required by applicable law or agreed to in writing,
013 *   software distributed under the License is distributed on an
014 *   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *   KIND, either express or implied.  See the License for the
016 *   specific language governing permissions and limitations
017 *   under the License.
018 *
019 */
020package org.apache.mina.example.imagine.step1.codec;
021
022import org.apache.mina.filter.codec.ProtocolEncoderOutput;
023import org.apache.mina.filter.codec.ProtocolEncoderAdapter;
024import org.apache.mina.core.buffer.IoBuffer;
025import org.apache.mina.core.session.IoSession;
026import org.apache.mina.example.imagine.step1.ImageResponse;
027
028import javax.imageio.ImageIO;
029import java.awt.image.BufferedImage;
030import java.io.ByteArrayOutputStream;
031import java.io.IOException;
032
033/**
034 * an encoder for {@link ImageResponse} objects 
035 *
036 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
037 */
038public class ImageResponseEncoder extends ProtocolEncoderAdapter {
039
040    public void encode(IoSession session, Object message, ProtocolEncoderOutput out) throws Exception {
041        ImageResponse imageResponse = (ImageResponse) message;
042        byte[] bytes1 = getBytes(imageResponse.getImage1());
043        byte[] bytes2 = getBytes(imageResponse.getImage2());
044        int capacity = bytes1.length + bytes2.length + 8;
045        IoBuffer buffer = IoBuffer.allocate(capacity, false);
046        buffer.putInt(bytes1.length);
047        buffer.put(bytes1);
048        buffer.putInt(bytes2.length);
049        buffer.put(bytes2);
050        buffer.flip();
051        out.write(buffer);
052    }
053
054    private byte[] getBytes(BufferedImage image) throws IOException {
055        ByteArrayOutputStream baos = new ByteArrayOutputStream();
056        ImageIO.write(image, "PNG", baos);
057        return baos.toByteArray();
058    }
059}