Java NIO 聊天室实例

超、凢脫俗 2022-08-18 11:32 4阅读 0赞

最近写了个Java NIO聊天室聊天的程序，NIO学习起来比较困难的，我的代码能给大家起到一个抛砖引玉的作用！

服务端：

package test.javanio; 
    
    /** * @author * @version * CreateTime：2010-12-1 下午05:12:11 * Description： */ 
    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.util.Date; 
    import java.util.Iterator; 
    import java.util.logging.Level; 
    import java.util.logging.Logger; 
    
    public class MySocketServer implements Runnable {  
    
        private boolean running; 
    
        private Selector selector; 
        String writeMsg; 
        StringBuffer sb = new StringBuffer(); 
        SelectionKey ssckey; 
    
        public MySocketServer() {  
    
            running = true; 
    
        }  
    
        public void init() {  
            try {  
                selector = Selector.open(); 
                ServerSocketChannel ssc = ServerSocketChannel.open(); 
                ssc.configureBlocking(false); 
                ssc.socket().bind(new InetSocketAddress(2345)); 
                ssckey = ssc.register(selector, SelectionKey.OP_ACCEPT); 
                System.out.println("server is starting..." + new Date()); 
            } catch (IOException ex) {  
                Logger.getLogger(MySocketServer.class.getName()).log(Level.SEVERE,  
                        null, ex); 
            }  
        }  
    
        public static void main(String[] args) {  
            MySocketServer server = new MySocketServer(); 
            new Thread(server).start(); 
    
        }  
    
        public void execute() {  
            try {  
                while (running) {  
                    int num = selector.select(); 
                    if (num > 0) {  
                        Iterator<SelectionKey> it = selector.selectedKeys()  
                                .iterator(); 
                        while (it.hasNext()) {  
                            SelectionKey key = it.next(); 
                            it.remove(); 
                            if (!key.isValid())  
                                continue; 
                            if (key.isAcceptable()) {  
                                System.out.println("isAcceptable"); 
                                getConn(key); 
                            } else if (key.isReadable()) {  
                                System.out.println("isReadable"); 
                                readMsg(key); 
                            }  
    
                            else if (key.isValid() && key.isWritable()) {  
                                if (writeMsg != null) {  
                                    System.out.println("isWritable"); 
                                    writeMsg(key); 
                                }  
    
                            }  
    
                            else 
                                break; 
    
                        }  
    
                    }  
                    Thread.yield(); 
                }  
    
            } catch (IOException ex) {  
                Logger.getLogger(MySocketServer.class.getName()).log(Level.SEVERE,  
                        null, ex); 
            }  
        }  
    
        private void getConn(SelectionKey key) throws IOException {  
            ServerSocketChannel ssc = (ServerSocketChannel) key.channel(); 
            SocketChannel sc = ssc.accept(); 
            sc.configureBlocking(false); 
            sc.register(selector, SelectionKey.OP_READ); 
            System.out.println("build connection :" 
                    + sc.socket().getRemoteSocketAddress()); 
        }  
    
        private void readMsg(SelectionKey key) throws IOException {  
            sb.delete(0, sb.length()); 
            SocketChannel sc = (SocketChannel) key.channel(); 
            System.out.print(sc.socket().getRemoteSocketAddress() + " "); 
            ByteBuffer buffer = ByteBuffer.allocate(1024); 
            buffer.clear(); 
            int len = 0; 
            StringBuffer sb = new StringBuffer(); 
            while ((len = sc.read(buffer)) > 0) {  
                buffer.flip(); 
                sb.append(new String(buffer.array(), 0, len)); 
            }  
            if (sb.length() > 0)  
                System.out.println("get from client:" + sb.toString()); 
            if (sb.toString().trim().toLowerCase().equals("quit")) {  
                sc.write(ByteBuffer.wrap("BYE".getBytes())); 
                System.out.println("client is closed " 
                        + sc.socket().getRemoteSocketAddress()); 
                key.cancel(); 
                sc.close(); 
                sc.socket().close(); 
    
            } else {  
                String toMsg = sc.socket().getRemoteSocketAddress() + "said:" 
                        + sb.toString(); 
                System.out.println(toMsg); 
    
                writeMsg = toMsg; 
    
                /* * Iterator<SelectionKey> it=key.selector().keys().iterator(); * * while(it.hasNext()){ SelectionKey skey=it.next(); * if(skey!=key&&skey!=ssckey){ SocketChannel client=(SocketChannel) * skey.channel(); client.write(ByteBuffer.wrap(toMsg.getBytes())); * } * * } */ 
    
                /* * * key.attach(toMsg); * key.interestOps(key.interestOps()|SelectionKey.OP_WRITE); */ 
                Iterator<SelectionKey> it = key.selector().keys().iterator(); 
    
                while (it.hasNext()) {  
                    SelectionKey skey = it.next(); 
                    if (skey != key && skey != ssckey) {  
                        if (skey.attachment() != null) {  
                            String str = (String) skey.attachment(); 
                            skey.attach(str + toMsg); 
                        } else {  
                            skey.attach(toMsg); 
                        }  
                        skey  
                                .interestOps(skey.interestOps()  
                                        | SelectionKey.OP_WRITE); 
                    }  
    
                }  
                selector.wakeup();// 可有可无 
    
            }  
    
        }  
    
        public void run() {  
            init(); 
            execute(); 
        }  
    
        private void writeMsg(SelectionKey key) throws IOException {  
    
            System.out.println("++++enter write+++"); 
            SocketChannel sc = (SocketChannel) key.channel(); 
            String str = (String) key.attachment(); 
    
            sc.write(ByteBuffer.wrap(str.getBytes())); 
            key.interestOps(SelectionKey.OP_READ); 
        }  
    }

客户端：

package test.javanio;  
    
    /** * @author * @version * CreateTime：2010-12-1 下午05:12:46 * Description： */ 
    import java.io.BufferedReader;  
    import java.io.IOException;  
    import java.io.InputStreamReader;  
    import java.net.InetSocketAddress;  
    import java.nio.ByteBuffer;  
    import java.nio.channels.Selector;  
    import java.nio.channels.SocketChannel;  
    import java.util.logging.Level;  
    import java.util.logging.Logger;  
    import java.util.Currency.*;  
    
    public class MySocketClient implements Runnable {   
        Selector selector;  
    
        boolean running;  
    
        SocketChannel sc;  
    
        public MySocketClient() {  
            running = true;  
    
        }  
    
        public void init() {  
            try {  
                sc = SocketChannel.open();  
                sc.configureBlocking(false);  
                sc.connect(new InetSocketAddress("localhost", 2345));  
    
            } catch (IOException ex) {  
                Logger.getLogger(MySocketClient.class.getName()).log(Level.SEVERE,  
                        null, ex);  
            }  
        }  
    
        public static void main(String[] args) {  
    
            MySocketClient client = new MySocketClient();  
            new Thread(client).start();  
        }  
    
        public void execute() {  
    
            int num = 0;  
            try {  
                while (!sc.finishConnect()) {  
                }  
            } catch (IOException ex) {  
                Logger.getLogger(MySocketClient.class.getName()).log(Level.SEVERE,  
                        null, ex);  
            }  
    
            ReadKeyBoard rkb = new ReadKeyBoard();  
            new Thread(rkb).start();  
            while (running) {  
                try {  
    
                    ByteBuffer buffer = ByteBuffer.allocate(1024);  
                    buffer.clear();  
    
                    StringBuffer sb = new StringBuffer();  
                    Thread.sleep(500);  
    
                    while ((num = sc.read(buffer)) > 0) {  
                        sb.append(new String(buffer.array(), 0, num));  
                        buffer.clear();  
                    }  
                    if (sb.length() > 0)  
                        System.out.println(sb.toString());  
                    if (sb.toString().toLowerCase().trim().equals("bye")) {  
                        System.out.println("closed....");  
    
                        sc.close();  
                        sc.socket().close();  
                        rkb.close();  
                        running = false;  
                    }  
                } catch (InterruptedException ex) {  
                    Logger.getLogger(MySocketClient.class.getName()).log(  
                            Level.SEVERE, null, ex);  
                } catch (IOException ex) {  
                    Logger.getLogger(MySocketClient.class.getName()).log(  
                            Level.SEVERE, null, ex);  
                }  
            }  
    
        }  
    
        public void run() {  
            init();  
            execute();  
        }  
    
        class ReadKeyBoard implements Runnable {  
    
            boolean running2 = true;  
    
            public ReadKeyBoard() {  
    
            }  
    
            public void close() {  
                running2 = false;  
            }  
    
            public void run() {  
                BufferedReader reader = new BufferedReader(new InputStreamReader(  
                        System.in));  
                while (running2) {  
                    try {  
                        System.out.println("enter some commands:");  
                        String str = reader.readLine();  
                        sc.write(ByteBuffer.wrap(str.getBytes()));  
    
                    } catch (IOException ex) {  
                        Logger.getLogger(ReadKeyBoard.class.getName()).log(  
                                Level.SEVERE, null, ex);  
                    }  
                }  
    
            }  
    
        }  
    }

原文地址：[http://gcguchao8888-sina-com.iteye.com/blog/839021][http_gcguchao8888-sina-com.iteye.com_blog_839021]

[http_gcguchao8888-sina-com.iteye.com_blog_839021]: http://gcguchao8888-sina-com.iteye.com/blog/839021