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);
}
}
}
更多关于java相关内容感兴趣的读者可查看本站专题：《Java Socket编程技巧总结》、《Java文件与目录操作技巧汇总》、《Java数据结构与算法教程》、《Java操作DOM节点技巧总结》和《Java缓存操作技巧汇总》
希望本文所述对大家java程序设计有所帮助。
