code: public <V> V call(Callable<V> callable) throws Exception {
  		initStartTotal();
  		long startInvokation = System.currentTimeMillis();
  		V result = callable.call();
  		invoked(System.currentTimeMillis() - startInvokation);
  		return result;
  	}
docs: Measure the invokation time of the given Callable.