timing threadpool java

Question

I need to time the total time it takes for a method to complete, usually i use:

long startTime = System.currentTimeMillis();
MethodWithThreads(); // the method which uses threading
long endTime = System.currentTimeMillis();
total = endTime - startTime;

Now obiviously the problem is that the mainthread terminates before the rest of the threads. Inside the thread function is the following code:

int cores = Runtime.getRuntime().availableProcessors();
ExecutorService pool = Executors.newFixedThreadPool(cores-1);
for(int i = 0; i < 1000; i++)
     {
      pool.submit(new RunnableThread());
     }
pool.shutdown();

So how am i going to find the total time for the thread method to finish?

Answer 1

Stupid me... should have done more research. I used the isTerminated in a while loop and awaited termination.

 while(!pool.isTerminated())
            {
                try {
                 pool.awaitTermination(1000, TimeUnit.SECONDS);
                 } catch (InterruptedException ex) {
                    Logger.getLogger(ThreadManagement.class.getName()).log(Level.SEVERE,null, ex);
                 }
            }
            long endTime = System.currentTimeMillis();