4-5 功能完善

NioServer.java

package io.torey.niotest;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.*;
import java.nio.charset.Charset;
import java.util.Iterator;
import java.util.Set;
/**
 * NIO服务器端
 */
public class NioServer {
    public static void main(String[] args){
        NioServer nioServer = new NioServer();
        try {
            nioServer.start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    /**
     * 启动
     */
    public void start() throws IOException{
        //1 创建Selector
        //2 通过ServerSocketChannel创建channel通道
        //3 为channel通道绑定监听端口
        //4 重点：设置channel为非阻塞模式
        //5 将channel注册到selector上，监听连接事件
        //6 循环等待新接入的连接
        //7 根据就绪状态，调用对应方法处理业务逻辑
        //1 创建Selector
        Selector selector = Selector.open();
        //2 通过ServerSocketChannel创建channel通道
        ServerSocketChannel serverSocketChannel= ServerSocketChannel.open();
        //3 为channel通道绑定监听端口
        serverSocketChannel.bind(new InetSocketAddress(8000));
        //4 重点：设置channel为非阻塞模式
        serverSocketChannel.configureBlocking(false);
        //5 将channel注册到selector上，监听连接事件
        serverSocketChannel.register(selector,SelectionKey.OP_ACCEPT);
        System.out.println("服务器启动成功!!");
        //6 循环等待新接入的连接
        while (true) {
            //这个方法是阻塞方法，获取可用的channel数量
            int readyChannels= selector.select();
            if (readyChannels==0) {
                continue;
            }
            //获取可用channel的集合
            Set<SelectionKey> selectionKeys = selector.selectedKeys();
            Iterator<SelectionKey> iterator = selectionKeys.iterator();
            while (iterator.hasNext()) {
                //selectionKey的实例
                SelectionKey selectionKey = iterator.next();
                //移除Set中当前的selectionKey，重点
                iterator.remove();
                //7 根据就绪状态，调用对应方法处理业务逻辑
                //如果是 接入事件
                if (selectionKey.isAcceptable()) {
                    acceptHandler(serverSocketChannel,selector);
                }
                //如果是 可读事件
                if (selectionKey.isReadable()) {
                    readHandler(selectionKey,selector);
                }
            }
        }
    }
    /**
     * 接入事件处理器
     * @param serverSocketChannel
     * @param selector
     * @throws IOException
     */
    private void acceptHandler(ServerSocketChannel serverSocketChannel,Selector selector) throws IOException{
        //如果要是接入事件，创建socketChannel
        //将socketChannel设置为非阻塞工作模式
        //将channel注册到selector上，监听 可读事件
        //回复客户端提示信息
        System.out.println("有一个客户端进来了...");
        //如果要是接入事件，创建socketChannel
        SocketChannel socketChannel = serverSocketChannel.accept();
        //将socketChannel设置为非阻塞工作模式
        socketChannel.configureBlocking(false);
        //将channel注册到selector上，监听 可读事件
        socketChannel.register(selector,SelectionKey.OP_READ);
        //回复客户端提示信息
        socketChannel.write(Charset.forName("UTF-8")
                .encode("你与聊天室里其他人都不是朋友关系，请注意隐私安全!!"));
    }
    /**
     * 可读事件处理器
     */
    private void readHandler(SelectionKey selectionKey,Selector selector) throws IOException{
        //要从selectionKey中获取到已经就绪的channel
        //创建buffer
        //循环读取客户端请求信息
        //将channel再次注册到selector上，监听他的可读事件
        //将客户端发送的请求信息，广播给其他客户端
        //要从selectionKey中获取到已经就绪的channel
        SocketChannel socketChannel= (SocketChannel)selectionKey.channel();
        //创建buffer
        ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
        //循环读取客户端请求信息
        StringBuilder reques=new StringBuilder();
        while (socketChannel.read(byteBuffer) > 0) {
            //切换buffer为读模式
            byteBuffer.flip();
            //读取buffer中的内容
            reques.append(Charset.forName("UTF-8").decode(byteBuffer));
        }
        //将channel再次注册到selector上，监听他的可读事件
        socketChannel.register(selector,SelectionKey.OP_READ);
        //将客户端发送的请求信息，广播给其他客户端
        if (reques.length()>0) {
            String requesStr = reques.toString();
            System.out.println("收到客户端消息:"+requesStr);
            broadCast(selector,socketChannel,requesStr);
        }
    }
    /**
     * 广播给其他客户端
     */
    private void broadCast(Selector selector,SocketChannel sourceChannel,String request){
        //获取到所有已接入的客户端channel
        //循环向所有channel广播消息
        //获取到所有已接入的客户端channel
        Set<SelectionKey> selectionKeySet = selector.keys();
        selectionKeySet.forEach(selectionKey -> {
            SelectableChannel targetChannel = selectionKey.channel();
            //需要将发送消息的channel剔除掉，自己发的消息，广播的时候不在给自己发消息
            if (targetChannel instanceof SocketChannel
                    && targetChannel!=sourceChannel) {
                try {
                    //将消息发送到其他客户端
                    ((SocketChannel) targetChannel).write(Charset.forName("UTF-8").encode(request));
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });
        //循环向所有channel广播消息
    }
}

NioClientHandler.java

package io.torey.niotest;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.util.Iterator;
import java.util.Set;
/**
 * 服务器端线程类，专门接收服务器端响应
 */
public class NioClientHandler implements Runnable {
    private Selector selector;
    public NioClientHandler(Selector selector) {
        this.selector = selector;
    }
    @Override
    public void run() {
        try{
        while (true) {
            //这个方法是阻塞方法，获取可用的channel数量
            int readyChannels= selector.select();
            if (readyChannels==0) {
                continue;
            }
            //获取可用channel的集合
            Set<SelectionKey> selectionKeys = selector.selectedKeys();
            Iterator<SelectionKey> iterator = selectionKeys.iterator();
            while (iterator.hasNext()) {
                //selectionKey的实例
                SelectionKey selectionKey = iterator.next();
                //移除Set中当前的selectionKey，重点
                iterator.remove();
                //7 根据就绪状态，调用对应方法处理业务逻辑
                //如果是 可读事件
                if (selectionKey.isReadable()) {
                    readHandler(selectionKey,selector);
                }
            }
        }}catch (Exception ex){
            ex.printStackTrace();
        }
    }
    /**
     * 可读事件处理器
     */
    private void readHandler(SelectionKey selectionKey,Selector selector) throws IOException {
        //要从selectionKey中获取到已经就绪的channel
        //创建buffer
        //循环读取服务器端请求信息
        //将channel再次注册到selector上，监听他的可读事件
        //将服务器端发送的请求信息，广播给其他服务器端
        //要从selectionKey中获取到已经就绪的channel
        SocketChannel socketChannel= (SocketChannel)selectionKey.channel();
        //创建buffer
        ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
        //循环读取服务器端请求信息
        StringBuilder response=new StringBuilder();
        while (socketChannel.read(byteBuffer) > 0) {
            //切换buffer为读模式
            byteBuffer.flip();
            //读取buffer中的内容
            response.append(Charset.forName("UTF-8").decode(byteBuffer));
        }
        //将channel再次注册到selector上，监听他的可读事件
        socketChannel.register(selector,SelectionKey.OP_READ);
        //将服务器端发送的请求信息，打印到本地
        if (response.length()>0) {
            System.out.println("收到服务器端消息:"+response.toString());
        }
    }
}

NioClient.java

package io.torey.niotest;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.util.Scanner;
/**
 * NIO客户端
 */
public class NioClient {
    /**
     * 启动
     */
    public void start(String nickname) throws IOException {
        //连接服务器端
        //向服务器端发送数据
        //接收服务器端相应
        //连接服务器端
        SocketChannel socketChannel = SocketChannel.open(
                new InetSocketAddress("127.0.0.1", 8000));
        //接收服务器端相应
        //新开一个线程，专门负责来接收服务器端的相应数据
        Selector selector = Selector.open();
        socketChannel.configureBlocking(false);
        socketChannel.register(selector,SelectionKey.OP_READ);
        new Thread(new NioClientHandler(selector)).start();
        //向服务器端发送数据
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()) {
            String request =nickname+":"+ scanner.nextLine();
            if (null!= request&&request.length()>0) {
                socketChannel.write(Charset.forName("UTF-8").encode(request));
            }
        }
    }
}

AClient.java

package io.torey.niotest;
import java.io.IOException;
public class AClient {
    public static void main(String[] args) {
          NioClient client=new NioClient();
        try {
            client.start("客户端A");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

BClient.java

package io.torey.niotest;
import java.io.IOException;
public class AClient {
    public static void main(String[] args) {
          NioClient client=new NioClient();
        try {
            client.start("客户端B");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

测试截图