ObjectInputStream readObject loop

Question

When using the readObject method of ObjectInputStream the method blocks until it reads something from the stream.
how would i put this method in a test loop?
as when the method blocks and is waiting to read, if the output stream at the other end of the socket closes, then an IOException will be thrown.
is there something i can write like, while(input != EOF)?
cheers

Answer 1

There is no object that a readObject call could return to indicate that it was at end of file. On files the available method lets you know when no more data is available, this method can't be used with sockets since the sender may pause between objects. If the sender closes a Socket Exception: Connection reset will be thrown, you can catch this and terminate. A better choice is to define an object that meand end of transmission. But this is not always feasible, if you must be able to send any arbitrary object.
Here's an example of a simple object transfer
Sending class:
import java.io.*;
import java.net.*;
import java.util.*;
public class TestWO
     static public void main(String [] args)
          Socket sock;
          ObjectOutputStream oos;
          try
               sock = new Socket("127.0.0.1",5050);
               oos = new ObjectOutputStream(sock.getOutputStream());
               for(int i = 0; i<args.length; i++)
                    Thread.sleep(2000);
                    System.out.println("writing "+args);
                    oos.writeObject(args[i]);
          catch(Exception e){System.out.println(e);}
Receiving class:
import java.io.*;
import java.net.*;
import java.util.*;
public class TestRO
     Socket sock;
     ObjectInputStream ois;
     ServerSocket ss;
     private void listen(int port)
          System.out.println("Listening on port="+port);
          try
               ss = new ServerSocket(port);
               sock = ss.accept();
               System.out.println("call accepted");
               ss.close();
               receive();
          catch(Exception e){     e.printStackTrace();}
     static public void main(String [] args)
          new TestRO().listen(5050);
     void receive()
          System.out.println("starting receiver");
          try
               ois = new ObjectInputStream(sock.getInputStream());
          catch(IOException e)
               System.out.println(e);
               return;
          boolean running = true;
          Object obj;
          while(running)
               try
                    obj = ois.readObject();
                    System.out.println("object="+obj);
               catch(SocketException e)
                    if(e.getMessage().equals("Connection reset")){System.out.println("closed by partner");}
                    else e.printStackTrace();
                    running = false;
               catch(Exception ex){ex.printStackTrace(); running = false;}
          try
               ois.close();
               sock.close();
          catch(Exception e){}