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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.

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
 abstract void setLegs();
 //having body
 //may override or may not
 void setHead()

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
 void setLegs() {
  System.out.println("i have four legs");

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

 public String tellYourWeight(String weight) {
  return weight;




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