怎么使用Java NIO实现多人聊天室

本篇内容主要讲解“怎么使用Java NIO实现多人聊天室”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“怎么使用Java Nio实现多人聊天室”吧!

NIO服务端

public class NiOServer {        public void start() throws IOException {                Selector selector = Selector.open();                ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();                serverSocketChannel.bind(new InetSocketAddress(8000));                serverSocketChannel.configureBlocking(false);                serverSocketChannel.reGISter(selector, SelectionKey.OP_ACCEPT);        System.out.println("服务器启动成功！");                for (;;) { // while(true) c for;;                        int readyChannels = selector.select();                        if (readyChannels == 0) continue;                        Set<SelectionKey> selectionKeys = selector.selectedKeys();            Iterator iterator = selectionKeys.iterator();            while (iterator.hasNext()) {                                SelectionKey selectionKey = (SelectionKey) iterator.next();                                iterator.remove();                                                if (selectionKey.isAcceptable()) {                    acceptHandler(serverSocketChannel, selector);                }                                if (selectionKey.isReadable()) {                    readHandler(selectionKey, selector);                }            }        }    }        private void acceptHandler(ServerSocketChannel serverSocketChannel,                               Selector selector)            throws IOException {                SocketChannel socketChannel = serverSocketChannel.accept();                socketChannel.configureBlocking(false);                socketChannel.register(selector, SelectionKey.OP_READ);                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"));    }        private void readHandler(SelectionKey selectionKey, Selector selector)            throws IOException {                SocketChannel socketChannel = (SocketChannel) selectionKey.channel();                ByteBuffer byteBuffer = ByteBuffer.allocate(1024);                String request = "";        while (socketChannel.read(byteBuffer) > 0) {                        byteBuffer.flip();                        request += Charset.forName("UTF-8").decode(byteBuffer);        }                socketChannel.register(selector, SelectionKey.OP_READ);                if (request.length() > 0) {            // 广播给其他客户端            broadCast(selector, socketChannel, request);        }    }        private void broadCast(Selector selector,                           SocketChannel sourceChannel, String request) {                Set<SelectionKey> selectionKeySet = selector.keys();                selectionKeySet.forEach(selectionKey -> {            Channel targetChannel = selectionKey.channel();            // 剔除发消息的客户端            if (targetChannel instanceof SocketChannel                    && targetChannel != sourceChannel) {                try {                    // 将信息发送到targetChannel客户端                    ((SocketChannel) targetChannel).write(                            Charset.forName("UTF-8").encode(request));                } catch (IOException e) {                    e.printStackTrace();                }            }        });    }        public static void main(String[] args) throws IOException {        new NioServer().start();    }}

NIO客户端

public class Nioclient {        public void start(String nickname) throws IOException {                SocketChannel socketChannel = SocketChannel.open(                new InetSocketAddress("127.0.0.1", 8000));                // 新开线程，专门负责来接收服务器端的响应数据        // selector ， socketChannel ， 注册        Selector selector = Selector.open();        socketChannel.configureBlocking(false);        socketChannel.register(selector, SelectionKey.OP_READ);        new Thread(new NioClientHandler(selector)).start();                Scanner scanner = new Scanner(System.in);        while (scanner.hasNextLine()) {            String request = scanner.nextLine();            if (request != null && request.length() > 0) {                socketChannel.write(                        Charset.forName("UTF-8")                                .encode(nickname + " : " + request));            }        }    }    public static void main(String[] args) throws IOException {//        new NioClient().start();    }}

客户端线程，处理服务器端响应的的消息

public class NioClientHandler implements Runnable {    private Selector selector;    public NioClientHandler(Selector selector) {        this.selector = selector;    }    @Override    public void run() {        try {            for (;;) {                int readyChannels = selector.select();                if (readyChannels == 0) continue;                                Set<SelectionKey> selectionKeys = selector.selectedKeys();                Iterator iterator = selectionKeys.iterator();                while (iterator.hasNext()) {                                        SelectionKey selectionKey = (SelectionKey) iterator.next();                                        iterator.remove();                                                            if (selectionKey.isReadable()) {                        readHandler(selectionKey, selector);                    }                }            }        } catch (IOException e) {            e.printStackTrace();        }    }        private void readHandler(SelectionKey selectionKey, Selector selector)            throws IOException {                SocketChannel socketChannel = (SocketChannel) selectionKey.channel();                ByteBuffer byteBuffer = ByteBuffer.allocate(1024);                String response = "";        while (socketChannel.read(byteBuffer) > 0) {                        byteBuffer.flip();                        response += Charset.forName("UTF-8").decode(byteBuffer);        }                socketChannel.register(selector, SelectionKey.OP_READ);                if (response.length() > 0) {            System.out.println(response);        }    }}

我们定义三个客户端，模拟三个用户在聊天室发送消息

public class AClient {    public static void main(String[] args)            throws IOException {        new NioClient().start("AClient");    }}public class BClient {    public static void main(String[] args)            throws IOException {        new NioClient().start("BClient");    }}public class CClient {    public static void main(String[] args)            throws IOException {        new NioClient().start("CClient");    }}

到此，相信大家对“怎么使用Java NIO实现多人聊天室”有了更深的了解，不妨来实际操作一番吧！这里是编程网网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！