title: Add delay to start execution thread with ScheduledExecutorService object
body: <p>I’m implementing a pool of thread to send multiple get snmp. I’m using the Callable objects: </p>
  
  <pre><code>final ScheduledExecutorService executor = Executors.newScheduledThreadPool(size);
  final Map&lt;String, Future&lt; &gt;&gt; map = new HashMap&lt;String, Future&lt; &gt;&gt;();
  for (final String key : groupMap.keySet()) {
      final ObjectCallable objectCallable = new ObjectCallable(par1, par2, par3);
      try {
           Thread.sleep(50);
      } catch (final InterruptedException e) {
             LOGGER.error("Error delay in the submit Callable" + e.getMessage());
              }
      final Future&lt; &gt; result = executor.submit(objectCallable);
  }
  </code></pre>
  
  <p>I need to add an execution delay between threads. I added a sleep before submit, it is correct? Someone knows some other method?</p>