socket基本通信

1.服务端
        while(true){
                       
                        Socket socket = null;
                        socket = serverSocket.accept();
                        InputStream iStream = socket.getInputStream();
                        byte[] buff = new byte[1024];
                        int len = -1;
                        StringBuffer pp = new StringBuffer();
                        while((len = iStream.read(buff))!=-1){                //read 方法返回的是读到的字符数
                                pp.append(new String(buff,0,len));            //所以这里采用这种方式来做
                        }
                        System.out.println(pp.toString());
                        OutputStream oStream = socket.getOutputStream();
                        oStream.write("back".getBytes());
                        socket.shutdownOutput();
                        System.out.println(socket.isClosed());
                        socket.close();

                }

要点：
        1.两端通信的时候最好是采用同样的方式。
        2.一端给另一端发信息的时候，最好采用 socket.shutdownOutput();这样另一端才会接受到，或者采用socket.close();
    不过在服务器端，最好是采用socket.shutdownOutput(),因为这样不会关闭socket，socket的关闭给客户端来做，减少通信的开销。
    如果一定要关闭服务端的socket，那么就放在finlly{}块中。   
 
2.客户端

                        Socket socket = new Socket("127.0.0.1",9001);
                        OutputStream oStream = socket.getOutputStream();
                        oStream.write("abc".getBytes());
//                        oStream.close();
                        socket.shutdownOutput();                //最好是采用这种做法
                        System.out.println(socket.isClosed());
//                        oStream.flush();
//                        socket.shutdownOutput();
                        InputStream iStream = socket.getInputStream();
                        byte[] buff = new byte[1024];
                        int len = -1;
                        StringBuffer pp = new StringBuffer();
                        while((len = iStream.read(buff))!=-1){
                                pp.append(new String(buff,0,len)); //最好是采用这种方式
                        }
                        System.out.println(pp.toString());
                        socket.close();


一 注意的一点：在使用 PrintWriter && BufferedReader 的时候最好设置
        PrintWriter pWriter = new PrintWriter(oStream,true); 设置为true 直接发送，不必等到缓冲区满
二 如果关闭了 OutputStream oStream = socket.getOutputStream();
        oStream 也相当于关闭了socket.





使用 BufferedReader && PrintWriter

1.BufferedReader 通过
       
                                String msg = null;
                                while((msg=br.readLine())!=null){ //通过readLine来读取
                                        System.out.println(msg);
                                        pw.println(msg+"1111");   //通过pringln推送到另一端，而不是write()方法是写入到一个字符串中，不是发送到另一端    
                                        socket.shutdownOutput();
                                }

评论

1 楼 cunjia 2010-09-27  

请问下，为什么不加socket.shutdownOutput()句服务器就收不到信息？
服务器用的NIO多线程实现，
当我加上socket.shutdownOutput()虽然服务器能收到客户端的消息，但客户端就退出了它的线程，这是什么原因呢？