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.sumup.codec;
021
022import org.apache.mina.core.buffer.IoBuffer;
023import org.apache.mina.core.session.IoSession;
024import org.apache.mina.example.sumup.message.AbstractMessage;
025import org.apache.mina.example.sumup.message.AddMessage;
026import org.apache.mina.filter.codec.ProtocolDecoderOutput;
027import org.apache.mina.filter.codec.demux.MessageDecoder;
028
029/**
030 * A {@link MessageDecoder} that decodes {@link AddMessage}.
031 *
032 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
033 */
034public class AddMessageDecoder extends AbstractMessageDecoder {
035
036    public AddMessageDecoder() {
037        super(Constants.ADD);
038    }
039
040    @Override
041    protected AbstractMessage decodeBody(IoSession session, IoBuffer in) {
042        if (in.remaining() < Constants.ADD_BODY_LEN) {
043            return null;
044        }
045
046        AddMessage m = new AddMessage();
047        m.setValue(in.getInt());
048        return m;
049    }
050
051    public void finishDecode(IoSession session, ProtocolDecoderOutput out)
052            throws Exception {
053    }
054}