question: public < V > Future < V > invoke ( String method , String path , Map < String , ? > arguments , ResultHandler < V > resultHandler ) { if ( method == null ) { throw new IllegalArgumentException ( ) ; } if ( path == null ) { throw new IllegalArgumentException ( ) ; } if ( arguments == null ) { throw new IllegalArgumentException ( ) ; } return executorService . submit ( new InvocationCallback < > ( method , path , arguments , resultHandler ) ) ; }
target:  Executes a service operation.