Socket(InetAddress address, int port);
　　Socket(InetAddress address, int port, boolean stream);
　　Socket(String host, int prot);
　　Socket(String host, int prot, boolean stream);
　　Socket(SocketImpl impl)
　　Socket(String host, int port, InetAddress localAddr, int localPort)
　　Socket(InetAddress address, int port, InetAddress localAddr, int localPort)
　　ServerSocket(int port);
　　ServerSocket(int port, int backlog);
　　ServerSocket(int port, int backlog, InetAddress bindAddr)

package me.socketthread;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
public class MultiSocketServer {
 public static void main(String[] args) {
  ServerSocket s = null;
  Socket socket = null;
  try {
   s=new ServerSocket(4567);
   System.out.println("ServerSocket Start:"+s);
   //等待请求,此方法会一直阻塞,直到获得请求才往下走 
   socket=s.accept();
   System.out.println("得到客户端地址:"+socket.getInetAddress());
   //调用线程类
   new ServerSocketThread(socket).start();
  }
  catch (Exception e) {
   try {
    socket.close();
   }
   catch (IOException e1) {
    // TODO Auto-generated catch block 
    e1.printStackTrace();
   }
  }
  finally{
   try {
    s.close();
   }
   catch (IOException e) {
    // TODO Auto-generated catch block 
    e.printStackTrace();
   }
  }
 }
}

package me.socketthread;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
public class ServerSocketThread extends Thread{
 private Socket socket = null;
 private BufferedReader br = null;
 private PrintWriter pw = null;
 //声明构造函数,接收客户端请求socket
 public ServerSocketThread(Socket s)
  {
  this.socket=s;
 }
 @Override
  public void run() {
  //while(true){ 
  try {
   //注意此处得到的socket的输入流为socket的输入流即上方的(private Socket socket = null; )
   br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
   //向客户端返回消息的PrintWriter对象
   pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);
   String str = br.readLine();
   /* if(str.equals("END")){ 
     br.close(); 
     pw.close(); 
     socket.close(); 
     break; 
    } */
   System.out.println("Client Socket Message:"+str);
   pw.println("Message Received");
   pw.flush();
  }
  catch (Exception e) {
   try {
    br.close();
    pw.close();
    socket.close();
   }
   catch (IOException e1) {
    // TODO Auto-generated catch block 
    e1.printStackTrace();
   }
  }
  // }
 }
}

package me.socketthread;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
public class MultiClientSocket {
 public static void main(String[] args) {
  Socket socket = null;
  BufferedReader br = null;
  PrintWriter pw = null;
  try {
   socket=new Socket("127.0.0.1",4567);
   System.out.println("Socket=" + socket);
   //用于发送给server端的信息
   pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);
   //用于接收Server端发来的信息 
   br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
   // for (int i = 0; i < 10; i++) {
   //注意首先向服务端发送消息,再接收服务端返回的休息,不要写反了
   pw.println("howdy ");
   pw.flush();
   //flush()一般用于处理中时需要将数据立即写出。将缓冲区的内容输出
   String str = br.readLine();
   System.out.println("拿到server返回的消息:"+str);
   // } 
   // pw.println("END"); 
   // pw.flush();
  }
  catch (UnknownHostException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  finally {
   try {
    System.out.println("close......");
    br.close();
    pw.close();
    socket.close();
   }
   catch (IOException e) {
    // TODO Auto-generated catch block 
    e.printStackTrace();
   }
  }
 }
}

ServerSocket Start:ServerSocket[addr=0.0.0.0/0.0.0.0,localport=4567]

Socket=Socket[addr=/127.0.0.1,port=4567,localport=55258]
拿到server返回的消息:Message Received
close......

ServerSocket Start:ServerSocket[addr=0.0.0.0/0.0.0.0,localport=4567]
得到客户端地址:/127.0.0.1
Client Socket Message:howdy