如何判断浏览器的请求头是不是结束

\r\n\r\n好像是结束符

package com.maple.detail3;
 
 
 
 
 import java.io.FileInputStream;
 
 
 import java.io.FileNotFoundException;
 
 
 import java.io.IOException;
 
 
 import java.io.InputStream;
 
 
 import java.io.OutputStream;
 
 
 import java.io.PrintWriter;
 
 
 import java.net.ServerSocket;
 
 
 import java.net.Socket;
 
 
 
 
 public 
 class TcpServer3 {
 
     
 public 
 static 
 void main(String[] args) 
 throws Exception {
 
 
 
         ServerSocket serverSocket=
 new ServerSocket(10000);
 
         Thread t=
 null;
 
         
 while(
 true)
 
         {
 
             Socket socket=serverSocket.accept();
 
              t=
 new Thread(
 new ReadPic(socket));
 
              t.start();
 
         }
 
     }
 
 
 
 }
 
 
 
 
 class ReadPic 
 implements Runnable
 
 {
 
     Socket socket=
 null;
 
     
 
     
 public ReadPic(Socket socket) {
 
         
 this.socket=socket;
 
     }
 
 
 
     @Override
 
     
 public 
 void run() {
 
         
 try {
 
             OutputStream outputStream=socket.getOutputStream();
 
             InputStream inputStream=
 new FileInputStream("c:/2.png");
 
             
 
             InputStream socketInputStream=socket.getInputStream();
 
             
 
             
 
             
 byte[] buf=
 new 
 byte[1024];
 
             
 int len=0;
 
             
 
             
 while((len=socketInputStream.read(buf))!=-1)
 
             {
 
                 String line=
 new String(buf,0,len);
 
                 System.out.println(line.length()+"  "+line);
 
                 
 if
 (line.endsWith("\r\n\r\n"))
 
                 {
 
                     System.out.println("game is over");
 
                     
 break;
 
                 }
 
             }            
 
             System.out.println("kkkkkkkkkkkkkkkk");
 
             
 while((len=inputStream.read(buf))!=-1)
 
             {
 
                 outputStream.write(buf,0,len);
 
                 outputStream.flush();
 
             }
 
             socket.close();
 
         } 
 catch (Exception e) {
 
             e.printStackTrace();
 
         }
 
     }
 
 }