Java基于Socket实现简单的多线程回显服务器功能示例_Java教程

本文实例讲述了Java基于Socket实现简单的多线程回显服务器功能。分享给大家供大家参考，具体如下：

需要两个类，一个是EchoServer，代表服务器。另外一个是EchoServerClient，代表客户端。代码如下：

									package interview;

									import java.io.BufferedReader;

									import java.io.IOException;

									import java.io.InputStreamReader;

									import java.io.PrintWriter;

									import java.net.ServerSocket;

									import java.net.Socket;

									public class EchoServer {

									  public static void main(String []args) throws IOException{

									    ServerSocket server = new ServerSocket(6789);

									    while(true){

									      Socket client = server.accept();

									      ClientHandler handler = new ClientHandler(client);

									      new Thread(handler).start();

									    }

									  }

									  public static class ClientHandler implements Runnable{

									    private Socket client;

									    @Override

									    public void run() {

									      InputStreamReader isr = null;

									      try {

									        isr = new InputStreamReader(client.getInputStream());

									        BufferedReader br = new BufferedReader(isr);

									        PrintWriter pw = new PrintWriter(client.getOutputStream());

									        String msg = br.readLine();

									        System.out.println("收到" + client.getInetAddress() + "发送的" + msg);

									        pw.println("收到了你发的" + msg);

									        pw.flush();

									      } catch (IOException e) {

									        e.printStackTrace();

									      }

									    }

									    public ClientHandler(Socket client){

									      this.client = client;

									    }

									  }

									}

下面是客户端代码：

									package interview;

									import java.io.BufferedReader;

									import java.io.IOException;

									import java.io.InputStreamReader;

									import java.io.PrintWriter;

									import java.net.Socket;

									import java.net.UnknownHostException;

									import java.util.Scanner;

									public class EchoServerClient {

									  public static void main(String []args) throws UnknownHostException, IOException{

									    Socket client = new Socket("127.0.0.1", 6789);

									    Scanner sc = new Scanner(System.in);

									    System.out.print("请输入要发送的内容：");

									    String msg = sc.nextLine();

									    sc.close();

									    PrintWriter pw = new PrintWriter(client.getOutputStream());

									    pw.println(msg);

									    pw.flush();

									    InputStreamReader isr = new InputStreamReader(client.getInputStream());

									    BufferedReader br = new BufferedReader(isr);

									    System.out.println("服务器返回：" + br.readLine());

									    client.close();

									  }

									}

NIO多路复用套接字方法如下：

									package interview;

									import java.io.IOException;

									import java.net.InetSocketAddress;

									import java.nio.ByteBuffer;

									import java.nio.CharBuffer;

									import java.nio.channels.SelectionKey;

									import java.nio.channels.Selector;

									import java.nio.channels.ServerSocketChannel;

									import java.nio.channels.SocketChannel;

									import java.nio.charset.CharacterCodingException;

									import java.nio.charset.Charset;

									import java.nio.charset.CharsetDecoder;

									import java.nio.charset.CharsetEncoder;

									import java.util.Iterator;

									public class EchoServerNIO {

									  private static ServerSocketChannel serverChannel = null;

									  private static Selector selector = null;// 多路复用选择器

									  private static ByteBuffer buffer = null;  // 缓冲区

									  public static void main(String []args) throws IOException{

									    init();

									    listen();

									  }

									  static void init() throws IOException{

									    serverChannel = ServerSocketChannel.open();

									    buffer = ByteBuffer.allocate(1024);

									    serverChannel.socket().bind(new InetSocketAddress(6789));

									    serverChannel.configureBlocking(false);

									    selector = Selector.open();

									    serverChannel.register(selector, SelectionKey.OP_ACCEPT);

									  }

									  static void listen() throws IOException{

									    while(true){

									      if(selector.select(5000) != 0){

									        Iterator<SelectionKey> it = selector.selectedKeys().iterator();

									        while(it.hasNext()){

									          SelectionKey key = it.next();

									          it.remove();

									          handleKey(key);

									        }

									      }

									    }

									  }

									  static void handleKey(SelectionKey key) throws IOException{

									    SocketChannel channel = null;

									    if(key.isAcceptable()){

									      ServerSocketChannel serverChannel = (ServerSocketChannel)key.channel();

									      channel = serverChannel.accept();

									      channel.configureBlocking(false);

									      channel.register(selector, SelectionKey.OP_READ);

									    }else if(key.isReadable()){

									      channel = (SocketChannel)key.channel();

									      buffer.clear();

									      if(channel.read(buffer) > 0){

									        buffer.flip();

									        CharBuffer charBuffer = CharsetHelper.decode(buffer);

									        String msg = charBuffer.toString();

									        System.out.println("收到" + channel.getRemoteAddress() + "的消息:" + msg);

									        channel.write(CharsetHelper.encode(CharBuffer.wrap("received your msg:" + msg)));

									      }

									    }

									  }

									  public static class CharsetHelper{

									    private static final String UTF_8 = "UTF-8";

									    private static CharsetEncoder encoder = Charset.forName(UTF_8).newEncoder();

									    private static CharsetDecoder decoder = Charset.forName(UTF_8).newDecoder();

									    private CharsetHelper() {

									    }

									    public static ByteBuffer encode(CharBuffer in) throws CharacterCodingException{

									      return encoder.encode(in);

									    }

									    public static CharBuffer decode(ByteBuffer in) throws CharacterCodingException{

									      return decoder.decode(in);

									    }

									  }

									}