V - the result type of method call@FunctionalInterface public static interface Remote.Callable<V> extends Callable<V>, Serializable
call.
 The Callable interface is similar to Runnable, in that both are designed for classes whose
 instances are potentially executed by another thread.  A
 Runnable, however, does not return a result and cannot
 throw a checked exception.
 
The Executors class contains utility methods to
 convert from other common forms to Callable classes.