What is interface in Java ?

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What is interface in Java ?

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обновлено: 23 November 2025

An interface is an abstraction (a set of methods without a body).
The interface keyword is used to define the interface.

Example

Java

interface Book
{
     String GetAuthorName();
     String GetBookName();
     int GetPrice();
}

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Directly in the code (at runtime) we make an implementation for the interface | Java

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