Skip to main content

Difference between Abstract Class and Interface


Difference between Abstract Class and Interface

Difference between abstract class and interface ?

Abstract Class:-

1) Can have abstract and non-abstract method both.
2) One class can extend at most one class.
3) can declare non abstract method and also can define body for it.


Interface:-
1) can have only abstract method.
2) One class can implement multiple interfaces.
3) can't delare body to a method.

Please look below example for more understanding:-



package Basics;

public abstract class Animal {

 int  head;
 //no body (unimplemented function need to override in child class as a
 //compulsion
 abstract void setLegs();
 
 //having body
 //may override or may not
 void setHead()
 {
  head=1;
 }
 
 
 
}


package Basics;

// can have only methods and by default all are abstract need to be override
//by implementing class, unlike abstract no method can havedefinition
public interface Pet {

 void tellWhereAreYouFrom(String place);
 String tellYourWeight(String weight);
 
}

package Basics;


// can extend one class but can implement multiple interface
public class Dog extends Animal implements Pet{

 //must override all abstract methods from Parent class
 @Override
 void setLegs() {
  
  System.out.println("i have four legs");
  
 }

 //must override all methods from an interface
 @Override
 public void tellWhereAreYouFrom(String place) {
  System.out.println("My place is"+place);
  
 }

 @Override
 public String tellYourWeight(String weight) {
  
  return weight;
 }

}

Comments

.

Popular posts from this blog

How to design a Node in Tree?

How to design a Node in Tree?

There are three main components of a tree in a node.

 1) Integer holding data.
2) Left pointer holding node in a left subtree.
3) Right pointer holding node in a right subtree.

The following design is having data of int type and left,right pointers of a node to the subtrees.


package com.BST;publicclassNode{int data; Node left; Node right;/** * @return the data */publicNode(int data){this.left=null;this.right=null;this.data=data;}publicintgetData(){return data;}/** * @param data the data to set */publicvoidsetData(int data){this.data= data;}/** * @return the left */public Node getLeft(){return left;}/** * @param left the left to set */publicvoidsetLeft(Node left){this.left= left;}/** * @return the right */public Node getRight(){return right;}/** * @param right the right to set */publicvoidsetRight(Node right){this.right= right;}/* (non-Javadoc) * @see java.lang.Object#toString() */@Overridepublic String toString(){return"Node [data=&quo…

Heap implementation in JAVA

In this tutorial we will see all the functionalities of heaps implemented through java language.



package com.problems.heap;publicclassHeapFunctions{//Function to generate maxheapify where root is max than childspublicvoidmaxHeapify(int Arr[],int i,int N){int largest;int left =2*i+1;//left childint right =2*i +2;//right child System.out.println("left"+" "+left); System.out.println("right"+" "+right); System.out.println("Max size"+" "+N);if(left< N && Arr[left]> Arr[i]){ largest = left; System.out.println("largest left"+largest);}else{ largest = i; System.out.println("largest i"+largest);}if(right < N && Arr[right]> Arr[largest]){ largest = right; System.out.println("largest right"+largest);}if(largest != i ){ System.out.println("No largest"+largest); Arr=swap (A…