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Java abstract Keyword

❮ Java Keywords


Example

An abstract method belongs to an abstract class, and it does not have a body. The body is provided by the subclass:

// Code from filename: Main.java
// abstract class
abstract class Main {   public String fname = "John";   public int age = 24;   public abstract void study(); // abstract method } // Subclass (inherit from Main) class Student extends Main {   public int graduationYear = 2018;   public void study() { // the body of the abstract method is provided here     System.out.println("Studying all day long");   } } // End code from filename: Main.java // Code from filename: Second.java class Second {   public static void main(String[] args) {     // create an object of the Student class (which inherits attributes and methods from Main)     Student myObj = new Student();     System.out.println("Name: " + myObj.fname);     System.out.println("Age: " + myObj.age);     System.out.println("Graduation Year: " + myObj.graduationYear);     myObj.study(); // call abstract method   } }

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Definition and Usage

The abstract keyword is a non-access modifier, used for classes and methods.

Class: An abstract class is a restricted class that cannot be used to create objects (to access it, it must be inherited from another class).

Method: An abstract method can only be used in an abstract class, and it does not have a body. The body is provided by the subclass (inherited from).


Related Pages

Read more about modifiers in our Java Modifiers Tutorial.


❮ Java Keywords