extends keyword in java

The ” extends ” keyword is used in a class or interface declaration to indicate that the class or interface being declared is a subclass of the class or interface whose name follows the extends keyword.

In other words,
When declaring a class/interface as a subclass of another class/interface, the extends keyword is used.


  1. public class Shape
  2.  {
  4.  }
  6. public class Rectangle extends Shape
  7.  {
  9.  }
public class Shape

public class Rectangle extends Shape

In the above case, subclass “Rectangle” is extending “Shape” class using extends keyword

  1. interface Animal{
  3. }
  5. interface Reptile extends Animal
  6.  {
  8.  }
interface Animal{


interface Reptile extends Animal


In the above case, interface “Reptile” is extending “Animal” interface using extends keyword

Class extending another class uses “extends” keyword.

Interface extending another interface uses “extends” keyword.

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Karibasappa G C (KB)
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