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.ResultMessage; 026import org.apache.mina.filter.codec.ProtocolDecoderOutput; 027import org.apache.mina.filter.codec.demux.MessageDecoder; 028 029/** 030 * A {@link MessageDecoder} that decodes {@link ResultMessage}. 031 * 032 * @author <a href="http://mina.apache.org">Apache MINA Project</a> 033 */ 034public class ResultMessageDecoder extends AbstractMessageDecoder { 035 private int code; 036 037 private boolean readCode; 038 039 public ResultMessageDecoder() { 040 super(Constants.RESULT); 041 } 042 043 @Override 044 protected AbstractMessage decodeBody(IoSession session, IoBuffer in) { 045 if (!readCode) { 046 if (in.remaining() < Constants.RESULT_CODE_LEN) { 047 return null; // Need more data. 048 } 049 050 code = in.getShort(); 051 readCode = true; 052 } 053 054 if (code == Constants.RESULT_OK) { 055 if (in.remaining() < Constants.RESULT_VALUE_LEN) { 056 return null; 057 } 058 059 ResultMessage m = new ResultMessage(); 060 m.setOk(true); 061 m.setValue(in.getInt()); 062 readCode = false; 063 return m; 064 } else { 065 ResultMessage m = new ResultMessage(); 066 m.setOk(false); 067 readCode = false; 068 return m; 069 } 070 } 071 072 public void finishDecode(IoSession session, ProtocolDecoderOutput out) 073 throws Exception { 074 } 075}