find instance by thread name java

Question

I'm starting few threads in my Controller class. Before start each thread I want to check whether previously have I started MyClass run(). If I have started, then I need to find the instance of MyClass that is running. Because some other class also want to get done work from this same MyClass instance. (assume MyClass is running as a service. So it can have multiple requests coming in.)

Note that I have more than one MyClass instances running as threads. So I want to find the MyClass instance by Specific thread name(TH1 or TH2).

public class MyClass implements Runnable{
   public void run() { 
     .
     .
     .
   }
}

This is the class that start the threads.

public class Controller {
    private void threadStarter(int i) {
      MyClass  mclss;
      if (i==1) {

         mclss  = new MyClass();
         Thread   th     = new Thread(mclss , "TH1");
         th.start();

      } else {

         mclss  = new MyClass();
         Thread   th2    = new Thread(mclss , "TH2");
         th2.start();

      }
    }
} 

Answer 1

Java threads have an ID http://docs.oracle.com/javase/6/docs/api/java/lang/Thread.html#getId() . Maybe you could leverage that. However, if my application depends on previous instance, if any, running, then I would have an identifier in MyClass itself and then use it . e.g.

class MyClass implements Runnable {

int id = -1;

public synchronized int getId() {
 if(id == -1) {
 id = SomeSingleTon.getNextId();
 }
 return id;
}


public run() ...
//etc
}

And then in controller class you could check the instance ids, currently running. Maybe you will need a collection to store all running instances of MyClass. Hope you get the idea.