Facilitating composition and increasing object reusability by means of an event-driven object-oriented development

Abstract this paper described an event-driven object-oriented development which enhances reusability and object composition. Simple composition of objects by means of one class named object environment is suggested. Object openness and reusability is increased with designing objects that instead of invoking the behaviour of other objects with sending messages to them inform the object environment about interesting changes of values of its state variables.