客户端/服务器套接字。 不读或写

Question

First of all here are a my compilable projects .

IDE = Netbeans

I have serversocket in one project and client socket in second project.

ServerSocket Project's code Fragment:

showStatus(String status); is method which appends text to statusWindow (JTextArea);
Socket gameClientSocket,ObjectOutputStream gameoos and ObjectInputStream gameois is declared outside code fragment

Code:

 private void configureSockets() {
        try{
        properties.showStatus("GAME_THREAD-waiting someone to accept");
        gameClientSocket = gameSocket.accept();

        properties.showStatus("GAME_THREAD-Accepted");
        properties.showStatus("GAME_THREAD-getting outputsstreams");

        gameoos= new ObjectOutputStream(gameClientSocket.getOutputStream());
        gameoos.flush();
        properties.setGameStream(gameoos);


         properties.showStatus("GAME_THREAD-getting inputstreams");
         gameois=new ObjectInputStream(gameClientSocket.getInputStream());
         properties.showStatus("GAME_THREAD-testing connections ,\nwe must receive int 1 ");
         properties.showStatus("GAME_THREAD- received "+gameois.readInt());
         properties.showStatus("GAME_THREAD-tested");



        }catch(IOException ex){
            properties.showStatus(ex.getMessage());}
        }

And initialization:

gameSocket = new ServerSocket(GAME_PORT);

ClientSocket Project's code Fragment:

 System.out.println("GAME_THREAD-configuring gameSocket ");
                properties.showStatus("GAME_THREAD- configuring gameSocket ");
                if(gameSocket==null ){
                gameSocket = new Socket("localhost",GAME_PORT);
                System.out.println("GAME_THREAD- getting Streams");
                properties.showStatus("GAME_THREAD- getting Streams ");

                gameoos = new ObjectOutputStream(gameSocket.getOutputStream());
                gameoos.flush();
                gameois = new ObjectInputStream(gameSocket.getInputStream());

                properties.showStatus("GAME_THREAD-testing  sending  ");
                gameoos.writeInt(1);
                properties.showStatus("GAME_THREAD-seccessfully sent ");

                properties.showStatus("GAME_THREAD- setting Streams to gameWindow ");
                System.out.println("GAME_THREAD-setting Streams to gameWindow");
                properties.setGameStream(gameoos);
            }

At the end here are status Windows:

GAME_THREAD - blocking game Window
GAME_THREAD- configuring gameSocket 
GAME_THREAD- getting Streams 
GAME_THREAD-testing  sending  
GAME_THREAD-seccessfully sent 
GAME_THREAD- setting Streams to gameWindow 

And server Projects status Window:

GAME_THREAD-Accepted
GAME_THREAD-getting outputsstreams
GAME_THREAD-getting inputstreams
GAME_THREAD-testing connections ,
we must receive int 1 

PROBLEM:

I can't read a number from an ObjectInputStream (Or it's not writing), Exception is never thrown, process is freezing and don't doing anything. I don't know if I'm doing anything wrong. I searched the whole web but can't find any usable answer. Could you help me?

UPDATE:

gameoos.writeint(1);
gameoos.flush();

solved the problem

Answer 1

Freezing occurs because you are trying to do the network connection on the main thread I believe, which is a terrible plan - you need to put them on a second thread. You can either use a thread pool from the ExecutorService, http://www.journaldev.com/1069/java-thread-pool-example-using-executors-and-threadpoolexecutor or you can just run your own thread.

A thread needs an implementation of the Runnable interface to run.

public class MyThread implements Runnable
{
    @Override
    public void run()
    {
        //do stuff
    }
}

public static void main(String[] args)
{
    Thread thread = new Thread(new MyThread());
    thread.start();
    //...do other stuff and not end the app here
}

But I don't think you can send objects just like that, you would need to convert them to byte[] and reassemble them: send a serializable object over socket

My personal recommendation is to ditch the ObjectStreams altogether, and use a framework that allows for sending objects through as they are, like the KryoNet framework: https://github.com/EsotericSoftware/kryonet

An example code for using it would be this:

  Server server = new Server();
  Kryo kryo = server.getKryo();
  kryo.register(float[].class);
  server.start();
  server.bind(2300, 2301);
  server.addListener(new Listener() {
   public void received(Connection connection, Object object)
   {
      if(object instanceof float[])
      {
        float[] array = (float[])object;
        for(int i = 0; i < array.length; i++)
        {
           System.out.println("" + array[i]);
        }
      }        
   }});
  Client client = new Client();
  Kryo kryo = client.getKryo();
  kryo.register(float[].class);
  client.addListener(new Listener() {
    public void connected(Connection connection)
    {
       connection.sendTCP(new float[] {5, 6, 7, 8});
    }
  };
  client.connect(5000, "127.0.0.1”, 2300, 2301);

And KryoNet already runs networking on a background thread, so you don't need to mess around with that at all.