Multithread program with socket, help me

Question

Hi all, I have had some troubles with my multithread program, that is when I make 4 threads to send messages to 4 accepted ports: 2001, 2002, 2003 and 2004, it leads to the error:
"Java.net.SocketException: Software caused connection abort: recv fail"
I cannot understand why this exception is inconsistent. Please help me figure out
solution for this problem. Thank you.
Here is my code
public synchronized void sendREQMessage(Message obj)
     for(int i=2001;i<=2004;i++)
          try
                         obj.setPortDest(i);
                         myThread thread=new myThread(obj,i);
               catch (Exception e)
                    System.out.println(e);
public myThread(Message obj,int i)
          message=obj;
          port=i;
          start();
     public void run()
          try
               message.setPortDest(port);
               connection = new Socket("127.0.0.1",port);
               out = new ObjectOutputStream(
     connection.getOutputStream());               
               out.writeObject(message);
               out.flush();
               //connection.close();
          catch(Exception e)
               System.out.println(e);
     }

Answer 1

I'm sorry, I cannot understand what you mean.
Sometimes, the message can be sent well among 4 ports. Sometimes, it leads to the error:
"Java.net.SocketException: Software caused connection abort: recv fail"
And I don't know why.
Thank for your help