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Java program to create an abstract class with the constructor

Learn how to create an abstract class with the constructor in Java?
Submitted by Nidhi, on March 27, 2022

Problem Solution:

In this program, we will create an abstract class with an abstract method and constructor. Then we will implement the abstract method in a class by inheriting abstract class.

Program/Source Code:

The source code to create an abstract class with a constructor is given below. The given program is compiled and executed successfully.

// Java program to create an abstract class 
// with the constructor

abstract class AbsClass {
  abstract void MyFun();

  AbsClass() {
    System.out.println("AbsClass: constructor called");
  }
}

class Sample extends AbsClass {
  Sample() {
    System.out.println("Sample: constructor called");
  }

  void MyFun() {
    System.out.println("Sample: MyFun() called");
  }
}

public class Main {
  public static void main(String[] args) {
    AbsClass abs = new Sample();
    abs.MyFun();
  }
}

Output:

AbsClass: constructor called
Sample: constructor called
Sample: MyFun() called

Explanation:

In the above program, we created an abstract class AbsClass with an abstract method and constructor. Then we will inherit the AbsClass into Sample and implemented the MyFun() method.

The Main class contains a method main(). The main() method is the entry point for the program, here we created a reference of AbsClass and initialized it with the reference of Sample class. Then the constructor of AbsClass and MyFun() gets called. After that, we called MyFun() method using the reference of AbsClass.

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