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.reverser; 021 022import org.apache.mina.core.service.IoHandler; 023import org.apache.mina.core.service.IoHandlerAdapter; 024import org.apache.mina.core.session.IoSession; 025 026/** 027 * {@link IoHandler} implementation of reverser server protocol. 028 * 029 * @author <a href="http://mina.apache.org">Apache MINA Project</a> 030 */ 031public class ReverseProtocolHandler extends IoHandlerAdapter { 032 @Override 033 public void exceptionCaught(IoSession session, Throwable cause) { 034 // Close connection when unexpected exception is caught. 035 session.close(true); 036 } 037 038 @Override 039 public void messageReceived(IoSession session, Object message) { 040 // Reverse reveiced string 041 String str = message.toString(); 042 StringBuilder buf = new StringBuilder(str.length()); 043 for (int i = str.length() - 1; i >= 0; i--) { 044 buf.append(str.charAt(i)); 045 } 046 047 // and write it back. 048 session.write(buf.toString()); 049 } 050}