apache mina 2

Apache Mina入门MINA 

IoAccepter 相当于网络应用程序中的服务器端

IoConnector 相当于客户端

IoSession 当前客户端到服务器端的一个连接实例

IoHandler 业务处理逻辑

IoFilter 过滤器用于悬接通讯层接口与业务层接口

 

服务器端：MinaServer.java 
public class MinaServer { 
             private static final int SERVER_PORT = 9990; 
    
             public static void main(String[] args) throws Throwable{ 
                            //服务端入口 
                            IoAcceptor acceptor = new SocketAcceptor(); 
                            SocketAcceptorConfig cfg = new SocketAcceptorConfig(); 
                            cfg.setReuseAddress(true); 
                            //设定这个过滤器将以对象为单位读取数据 
                            cfg.getFilterChain().addLast("codec", 
new ProtocolCodecFilter(new ObjectSerializationCodecFactory())); 
                            //添加日志过滤器 
                            cfg.getFilterChain().addLast("logger", new LoggingFilter()); 
                            //接收访问的连接和到IoHandler触发事件 
             acceptor.bind(new InetSocketAddress(SERVER_PORT),new ServerHandler(), cfg); 
                            System.out.println("The server Listening on port " + SERVER_PORT); 
             } 
}    
     
服务器端业务处理类： 
public class ServerHandler extends IoHandlerAdapter 
{ 
             /** 
                * 有新连接时触发 
                */ 
             public void sessionOpened(IoSession session) { 
                            System.out.println("sessionOpened"); 
             } 
             /** 
                * 收到来自客户端的消息 
                */ 
             public void messageReceived(IoSession session, Object message) { 
                            System.out.println("server messageReceived!"); 
                            CityMessage cm = (CityMessage)message; 
                            System.out.println(cm.getCode()+":"+cm.getName()); 
                            //将消息发向客户端 
                            session.write(cm); 
             } 
             /** 
                * 当有异常发生时触发 
                */ 
             public void exceptionCaught(IoSession session, Throwable cause) { 
                            session.close(); 
             } 
             /** 
                * 连接被关闭时触发 
                */ 
             public void sessionClosed(IoSession ssn) throws Exception { 
                            System.out.println("session closed from " + ssn.getRemoteAddress()); 
             } 
}    
     
要发送的消息对象： 
public class CityMessage implements Serializable{ 
             private int code; 
             private String name; 
             public int getCode() { 
                            return code; 
             } 
             public void setCode(int code) { 
                            this.code = code; 
             } 
             public String getName() { 
                            return name; 
             } 
             public void setName(String name) { 
                            this.name = name; 
             } 
}    
     
客户端： 
public class MinaClient { 
             private static final String HOSTNAME = "localhost";         
        private static final int PORT = 9990;         
    
        public static void main( String[] args ) throws Throwable{         
                //Connector为客户端入口 
                     SocketConnector connector = new SocketConnector();                         
                SocketConnectorConfig cfg = new SocketConnectorConfig();         
                //设定这个过滤器将以对象为单位读取数据 
                cfg.getFilterChain().addLast("codec",    
                                                                                                                        new ProtocolCodecFilter( new ObjectSerializationCodecFactory() ) );         
                //添加日志过滤器 
                cfg.getFilterChain().addLast( "logger", new LoggingFilter() );         
                //向远程服务器发起连接，触发事件到IoHandler    
                connector.connect(new InetSocketAddress( HOSTNAME, PORT ),         
                                                new ClientHandler(), cfg );         
        }         
}    
     
客户端业务处理类： 
public class ClientHandler extends IoHandlerAdapter { 
             public ClientHandler() { 
                            super(); 
             } 
             /** 
                * 有新连接时触发 
                */ 
             public void sessionOpened(IoSession session) { 
                            // 创建一个cityMessage发送 
                            CityMessage cm = new CityMessage(); 
                            cm.setCode(547600); 
                            cm.setName("凤山"); 
                            session.write(cm); 
             } 
             /** 
                * 收到来自客户端的消息 
                */ 
             public void messageReceived(IoSession session, Object message) { 
                            System.out.println("client messageReceived!"); 
                            CityMessage cm = (CityMessage)message; 
                            System.out.println(cm.getCode()+":"+cm.getName()); 
             } 
             /** 
                * 当有异常发生时触发 
                */ 
             public void exceptionCaught(IoSession session, Throwable cause) { 
                            session.close(); 
             } 
             /** 
                * 连接被关闭时触发 
                */ 
             public void sessionClosed(IoSession ssn) throws Exception { 
                            System.out.println("session closed from " + ssn.getRemoteAddress()); 
             } 
}    

开发一个Mina应用，简单的说，就是创建连结，设定过滤规则，编写自己的消息处理器这三步！

 

过滤器：

ObjectSerializationCodecFactory：设定这个过滤器将以对象为单位读取数据。

TextLineCodecFactory：设定这个过滤器将一行一行(/r/n)的读取数据

 

注意：（摘抄自网上） 由apache mina建立的socket不管是采用TCP或是UDP，在Filter不添加codec选项的情况下，由IoHandlerAdapter派生的处理handler 类中public void messageReceived(IoSession session, Object message){}函数里的message对象是IoBuffer的实例，如下：

@Override 
        public void messageReceived(IoSession session, Object message) 
                        throws Exception { 

                if (! (message instanceof IoBuffer)) { 
                            return; 
                     } 

                IoBuffer rb = (IoBuffer) message; 
                callback.messageReceived(java.nio.ByteBuffer.wrap(rb.array(), 0, rb.buf().limit())); 
        }

如果你使用mina建立一个socket添加了如下：
IoFilter CODEC_FILTER = new ProtocolCodecFilter(
                new TextLineCodecFactory());
connector(acceptor).getFilterChain().addLast("codec", CODEC_FILTER);
如果发送数据的socket不是同样的设置或者不是利用mina建立的socket则发送数据的时候需要在数据末尾添加‘\n’，以表示字符串结束。