What do interfaces do in java

Implementing an interface allows a class to become more formal about the behavior it promises to provide. Interfaces form a contract between the class and the outside world, and this contract is enforced at build time by the compiler. If your class claims to implement an interface, all methods defined by that interface must appear in its source code before the class will successfully compile.

All rights reserved. Arrays in Java. Strings in Java. OOPS in Java. Constructors in Java. Interfaces in Java. Keywords in Java. Exception Handling in Java. Collection Framework. Multi-threading in Java. Table of Contents. Save Article. Improve Article. Like Article. Previous Encapsulation in Java. Next Nested Interface in Java. Recommended Articles. Article Contributed By :. The inventory interface would define, but not implement, methods that set and get the retail price, assign a tracking number, and so on.

To work in the inventory program, the bicycle class must agree to this protocol by implementing the interface. When a class implements an interface, the class agrees to implement all the methods defined in the interface. Note: To implement multiple interfaces, separate them with a comma see example below. We just launched W3Schools videos.

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