How to make room for other new threads?

Question

When I run my program for a relatively long period of time, a memory problem occurs!
There are a number of threads in my program running simultaneously (for example 16) created from a single class, and in every one of them, there are two different threads, which are responsible for some different periodic jobs. So I sleep them for a random time periodically, and they do that job in a repeating manner. On the other hand, each one of theses main (16) threads, invoke some methods of the other ones, with a random delay. In order to implement this delayed invocations, without blocking the hole thread itself, I use a Timer and its method, schedule(object, delay). In another class which I pass an instant of it as the first argument of schedule(object, delay), I invoke the method of another main thread (one of those 16 threads).
But the problem is after running my program for a while, this error shows up, and the program doesn't act normally after that:
"Exception in thread "Timer-11324(or some other number like this)" java.lang.OutOfMemoryError: unable to create new native thread"
What should I do? Does these Timers and their background threads dispose after their times passed? Or, should I dispose it manually? If it is so. how can I do that?
Thanks

Answer 1

There is a block of code like this in some methods of a class, which each of my 16 threads initiated from this class.
class Messaging
     int Broadcast_Delay;
     public void Broadcast()
          Timer Broadcast_Delay_Timer = new Timer();
          for(int i=0 ; i < 16 ; i++)
               //A random number between 0 and 100, generated by uniform distribution, as the timer delay
               Broadcast_Delay = StdRandom.uniform(0, 100);
               //Scheduling to run the run() method of an instance of class Broadcasting, with that random delay
               Broadcast_Delay_Timer.schedule(new Broadcasting(i, trigger_pid, trigger_inum), Broadcast_Delay);
class Broadcasting
     run()
}So a block of code like this runs a lot in my program, infinitely.
You are right, I put the declaration of these timers inside the methods in the main class, but they must be outside them!
You all were right!!!
But if I put the deceleration outside the methods, and directly in the main class, and if we invoke a method having this timer.schedule() continuously, is there a problem for last scheduled jobs?
Thanks