question: sets an executorservice to be used by this class . the executorservice passed to this method is used for executing thebackground task . thus it is possible to re-use an already existing executorservice or to use a specially configured one . if no executorservice is set , this instance creates a temporary one anddestroys it after background initialization is complete . note that this method must be called before #start ; otherwise an exception is thrown . concode_field_sep ExecutorService externalExecutor concode_elem_sep ExecutorService executor concode_elem_sep Future<T> future concode_elem_sep ExecutorService execFinally concode_field_sep T call concode_elem_sep Future<T> getFuture concode_elem_sep ExecutorService getExternalExecutor concode_elem_sep T get concode_elem_sep boolean start concode_elem_sep boolean isStarted concode_elem_sep T initialize concode_elem_sep ExecutorService getActiveExecutor concode_elem_sep ExecutorService createExecutor concode_elem_sep int getTaskCount concode_elem_sep Callable<T> createTask
target: void function ( final ExecutorService arg0 ) { if ( isStarted ( ) ) { throw new IllegalStateException ( "srini_string" ) ; } this . externalExecutor = arg0 ; }