Mina入门案例

原文出处：https://blog.youkuaiyun.com/cgwcgw_/article/details/18402769

本文记录的是采用mima实现客户端和服务端的通信，下面是具体的代码实现步骤：

服务端

package my.mina;

import org.apache.log4j.Logger;
import org.apache.mina.core.service.IoAcceptor;
import org.apache.mina.core.session.IdleStatus;
import org.apache.mina.filter.codec.ProtocolCodecFilter;
import org.apache.mina.filter.codec.textline.LineDelimiter;
import org.apache.mina.filter.codec.textline.TextLineCodecFactory;
import org.apache.mina.transport.socket.nio.NioSocketAcceptor;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.charset.Charset;

/**
 * @author: Linchong
 * @Date: 2018/7/10 15:06
 * @Description:
 */
public class Demo1Server {
    private static Logger logger = Logger.getLogger(Demo1Server.class);
    private static final int PORT = 3005;
    public static void main(String[] args) {
        IoAcceptor acceptor = null;
        try {
            // 1创建一个非阻塞的server端的Socket
            acceptor = new NioSocketAcceptor();
            // 2设置过滤器（使用Mina提供的文本换行符编解码器）
            acceptor.getFilterChain().addLast("codec",new ProtocolCodecFilter(new TextLineCodecFactory(
                    Charset.forName("UTF-8"),LineDelimiter.WINDOWS.getValue(),LineDelimiter.WINDOWS.getValue()
            )));
            // 3设置读取数据的缓冲区大小
            acceptor.getSessionConfig().setReadBufferSize(2048);
            // 4读写通道10秒内无操作进入空闲状态
            acceptor.getSessionConfig().setIdleTime(IdleStatus.BOTH_IDLE,10);
            // 5绑定逻辑处理器
            acceptor.setHandler(new Demo1ServerHandler());
            // 6绑定端口
            acceptor.bind(new InetSocketAddress(PORT));
            logger.info("服务器启动，port : "+PORT);
        } catch (IOException e) {
            logger.info("服务器启动失败...");
            e.printStackTrace();
        }
    }
}

服务端处理器

package my.mina;

import org.apache.log4j.Logger;
import org.apache.mina.core.service.IoHandlerAdapter;
import org.apache.mina.core.session.IoSession;

import java.util.Date;

/**
 * @author: Linchong
 * @Date: 2018/7/10 15:20
 * @Description:
 */
public class Demo1ServerHandler extends IoHandlerAdapter {
    private static Logger logger = Logger.getLogger(Demo1ServerHandler.class);
    private static final String BYE = "bye";
    @Override
    public void messageReceived(IoSession session, Object message) throws Exception {
        String msg = message.toString();
        logger.info("Server："+msg);
        if(BYE.equalsIgnoreCase(msg)) {
            session.close();
        }
        Date date = new Date();
        session.write(date);
    }

    @Override
    public void exceptionCaught(IoSession session, Throwable cause) throws Exception {
        super.exceptionCaught(session, cause);
    }


}

客户端

package my.mina;

import org.apache.log4j.Logger;
import org.apache.mina.core.future.ConnectFuture;
import org.apache.mina.core.service.IoConnector;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.filter.codec.ProtocolCodecFilter;
import org.apache.mina.filter.codec.textline.LineDelimiter;
import org.apache.mina.filter.codec.textline.TextLineCodecFactory;
import org.apache.mina.transport.socket.nio.NioSocketConnector;

import java.net.InetSocketAddress;
import java.nio.charset.Charset;

/**
 * @author: Linchong
 * @Date: 2018/7/10 15:35
 * @Description:
 */
public class Demo1Client {
    private static final Logger logger = Logger.getLogger(Demo1Client.class);
    private static final String ADDRESS = "127.0.0.1";
    private static final int PORT = 3005;

    public static void main(String[] args) {
        IoConnector connector = null;
        // 创建一个非阻塞的客户端程序
        connector = new NioSocketConnector();
        // 设置链接超时时间
        connector.setConnectTimeoutMillis(10000L);
        // 添加过滤器
        connector.getFilterChain().addLast("codec",new ProtocolCodecFilter(new TextLineCodecFactory(
                Charset.forName("UTF-8"),LineDelimiter.WINDOWS.getValue(),LineDelimiter.WINDOWS.getValue()
        )));
        // 添加业务逻辑处理器类
        connector.setHandler(new Demo1ClientHandler());
        IoSession session = null;
        try {
            //创建连接
            ConnectFuture future = connector.connect(new InetSocketAddress(ADDRESS,PORT));
            //等待连接创建完成
            future.awaitUninterruptibly();
            //获得session
            session = future.getSession();
            //发送消息
            session.write("Mima我喜欢你");
        } catch (Exception e) {
            logger.info("客户端连接异常...");
            e.printStackTrace();
        }
        // 等待连接断开
        session.getCloseFuture().awaitUninterruptibly();
        //该方法通过调用ExecutorService的shutdown()方法停止业务处理线程，并设置内部disposed标志位标识需要停止连接管理器；Worker线程通过该标识停止。
        connector.dispose();

    }
}

客户端处理器

package my.mina;

import org.apache.log4j.Logger;
import org.apache.mina.core.service.IoHandlerAdapter;
import org.apache.mina.core.session.IoSession;

/**
 * @author: Linchong
 * @Date: 2018/7/10 15:41
 * @Description:
 */
public class Demo1ClientHandler extends IoHandlerAdapter {
    private static final Logger logger = Logger.getLogger(Demo1ClientHandler.class);
    @Override
    public void exceptionCaught(IoSession session, Throwable cause) throws Exception {
        super.exceptionCaught(session, cause);
    }

    @Override
    public void messageReceived(IoSession session, Object message) throws Exception {
        String msg = message.toString();
        logger.info("Client:"+msg);
    }
}

---

总结

1、服务端

通过IoAcceptor的子类NioSocketAcceptor创建服务端socket，然后对它进行一系列的设置，例如设置过滤器（很多时候我们都需要自定义过滤器），设置逻辑处理器（创建一个IoHandler的子类，我们一般是继承IoHandler的子类IoHandlerAdapter，然后重写它的方法），读取缓存大小，绑定端口号等

2、客户端

和服务端很多地方相似，客户端是通过IoConnector的子类NioSocketConnector创建客户端socket，然后进行一系列的设置，例如设置链接超时时间、过滤器、逻辑处理类等，然后通过socket创建连接，通过session发送消息。

最后附上IoService接口主要继承结构图：