public < R > Stream < R > invokeAnd ( Function < C , R > invoker ) { Function < C , InvocationResult < R > > mapper = ( callbackInstance ) - > invoke ( callbackInstance , ( ) -> invoker . apply ( callbackInstance ) ) ; return this . callbackInstances . stream ( ) . map ( mapper ) . filter ( InvocationResult :: hasResult ) . map ( InvocationResult :: get ) ; }
Invoke the callback instances where the callback method returns a result .