In this section, we will learn what the extends keyword is and how it works in Java.
Note: we’re assuming you’re already familiar with Java inheritance in general.
What Is Extends Keyword in Java?
The `extends` keyword is used to make a class inherit from another one and hence be able to use its members.
Java extends Keyword Syntax:
class ChildClass extends ParentClass{/*...*/}
The extends keyword comes after the child class name and after that comes the name of the class we want the child class to inherit from.
Example: extending a class in Java
package com.example.demo; public class Child extends Parent{ public void sayHiChild(){ System.out.println("The child is saying Hi :)"); } }
Here, the Child class extended to the Parent class and hence, an instance of this class is able to use the public members of the `Parent` class as well.
Java extends vs implements
There’s another keyword in Java called `implements`. The main difference between the `extends` and the `implements` is that the second one is used when we want a class to use one or more Java interfaces, while the first one is used when we want a class to inherit from another class.
Note: you’ll learn more about this `implements` keyword in the interface section.