Inheritance Definition and Programs

• Getting the properties from one class object to other class is known as inheritance.
• In this inheritance will have parent class and child class so getting the properties of parent class object to child class object known as inheritance.
• Inheritance means to take something that already made.
• Inheritance can be implemented in java by using "extends" and "implements' keywords
• In this we have two types.
• Multilevel inheritance
• Multiple inheritance

Multilevel inheritance:

• Getting the properties from super class object to sub class object level wise with different priorities known as multiple inheritance.

Super class:

1. package instanceofjava; 
2. 
   
3. public class Super {
4.  
5.     int a,b;
6.  
7. void add(){
8.  
9.     System.out.println((a+b));
10.  
11. }
12.  
13. }

Sub class:

1. package instanceofjava;
2.  
3. public class Sub extends Super {
4.  
5. void show(){
6.  
7.       System.out.println("this is sub class show() method");
8.  
9. }
10.  
11. public static void main(String [] args){
12.  
13.        Sub obj= new Sub();
14.  
15.         obj.a=1;
16.         obj.b=2;
17.  
18.         obj.add();
19.         obj.show();
20.  
21.     }
22. }

Output:

1. 3
2. this is sub class show() method

Example program #2:

1. package instanceofjava;
2.  
3. public class A {
4.  
5.     int a,b;
6.  
7. public void show(){
8.  
9.   System.out.println("A class show method");
10.  
11. }
12.  
13. }

1. package instanceofjava;
2.  
3. public class B extends A{
4.  
5.  
6. public void print(){
7.  
8.   System.out.println("B class print method");
9.  
10. }
11.  
12. }

1. package instanceofjava;
2.  
3. public class C extends B{
4.  
5.  
6. public void display(){
7.  
8.   System.out.println("C class display method");
9.  
10. }
11. public static void main(String [] args){
12.  
13.  C obj= new C();
14.  
15.    obj.print();
16.    obj.show();
17.    obj.display();
18. 
    
19. }
20.  
21. }

Output:

1. B class print() method
2. A class show method
3. Class C display method

Multiple inheritance:

• Multiple inheritance means getting the properties from one class object to multiple class object with different priority.
• Multiple inheritance concept is not supported by java

1. package instanceofjava;
2.  
3. public class A {
4. 
   
5.  
6. public void show(){
7.  
8.   System.out.println("A class show method");
9.  
10. }
11.  
12. }

1. package instanceofjava;
2.  
3. public class b {
4.  
5. public void show(){
6.  
7.   System.out.println("B class show method");
8.  
9. }
10.  
11. }

1. package instanceofjava;
2.  
3. public class C extends A,B {  // not supported by java
4.  
5.  
6.  
7. public void print(){
8.  
9.   System.out.println("C class print method");
10.  
11. }
12.  
13. }

• Why java does not supports multiple inheritance check this for more information.

You Might Like:

1. Java Interview Programs On Core Java

2. Java Interview Programs On Collections 

3. What is The Output Of Following Programs Java Interview:

4. Java Concept and Example Program