Anonymous Inner class in Java

→ The anonymous class is also known as an anonymous inner class that means An inner class that is declared without a name is known as an anonymous class in java.

→ Inner class in java, which has no name is called Anonymous Inner class.

Important point:

Anonymous class has no name
It can be instantiated only once
It is usually declared inside a method or a code block, curly braces ending with a semicolon.
It does not have a constructor simply because it does not have a name.
It cannot be static.
It is accessible only at the point where it is defined.

→ Create Anonymous inner class in the following way :-

extending a class.
extending abstract class.
implementing interface

1) Example by extending a class:

    class Java {
   public void display() {
      System.out.println("All OOPs concepts");
   }}
class Php {
   public void show(){
      // creation of anonymous class extending class Java
      Java j = new Java() {
         public void display() {
            System.out.println("Php Like HTML.");
         }
      };
      j.display();
   }}
 class MainTest {
   public static void main(String[] args) {
       Php p = new Php();
       p.show();
       // Java j = new Java();
        //  j.display();
   }}

Output:-

Anonymous inner extending a class Example

2) Example by extending abstract class:

    abstract class Person{  
      abstract void eat();  
  }  
 class AbstractExample{  
   public static void main(String args[]){  
  Person p=new Person(){  
  void eat(){System.out.println("E library Portal ");}  
  };  
   p.eat();  
  }}  

Output:-

3) Example by implementing interface:

 interface Java {
   public void display();
 }
 class Php {
   public void show() {
      // anonymous class implementing interface
      Java j= new Java() {
         public void display() {
            System.out.println("Inside an anonymous class.");
         }
      };
        j.display();
   }}
  class MainEx {
   public static void main(String[] args) {
      Php an = new Php();
      an.show();
   }}

Output:-

Anonymous inner implementing interface Example

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