title: How is the cast working there even the eclipse is not flagging an error
body: <p>ThreadPoolExecutor threadPoolExecutor = (ThreadPoolExecutor)<br />
  Executors.newFixedThreadPool(numThreads);</p>
  <p>when i was looking through the api docs the fixedThreadPool() returns an instance of executor service but here we are casting the fixedThreadPool() to ThreadPoolExecutor it is weird since the ThreadPoolExecutor implements executor service can anyone explain me how this cast works??</p>