Interface: Interface is a reference type in Java, which contains a collection of abstract methods. It is very similar to class, but it cannot be instantiated, rather it is implemented by other classes. An interface needs to the follow certain conditions such as: • One cannot instantiate an interface. • Interfaces do not contain any constructors. • All methods present in the interface are abstracts. • An interface does not contain any instance field. • An interface cannot be extended by a class.

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Chapter 8.4, Problem 23STQ

Program Plan Intro

Interface:

Interface is a reference type in Java, which contains a collection of abstract methods. It is very similar to class, but it cannot be instantiated, rather it is implemented by other classes.

An interface needs to the follow certain conditions such as:

• One cannot instantiate an interface.

• Interfaces do not contain any constructors.

• All methods present in the interface are abstracts.

• An interface does not contain any instance field.

• An interface cannot be extended by a class.

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