What are the main underlying concepts of object orientation?
Objects, messages, class, inheritance and polymorphism are the main concepts of object orientation. What do u meant by “SBI” of an object? SBI stands for State, Behavior and Identity. Since every object has the above three. ? State: It is just a value to the attribute of an object at a particular time. ? Behaviour: It describes the actions and their reactions of that object. ? Identity: An object has an identity that characterizes its own existence. The identity makes it possible to distinguish any object in an unambiguous way, and independently from its state. Differentiate persistent & non-persistent objects? Persistent refers to an object’s ability to transcend time or space. A persistent object stores/saves its state in a permanent storage system with out losing the information represented by the object. A non-persistent object is said to be transient or ephemeral. By default objects are considered as non-persistent. What do you meant by active and passive objects? Active objects a
