To simplify the constructs that programmers have to learn for using paradigms, we extend methods to a new language construct, a method slot, to support both the event-handler paradigm and the aspect paradigm. A method slot is an object's property that can keep more than one function closure and be called like a method. We also propose a Java-based language, DominoJ, which replaces methods in Java with method slots, and explain the behavior of method slots and the operators. Then we evaluate the coverage of expressive ability of method slots by comparing DominoJ with other languages in detail. The feasibility of method slots is shown as well by implementing a prototype compiler and running a preliminary microbenchmark for it.