[Java] About anonymous classes

What is an anonymous class?

-~~ Also called an inner class or ~~ an anonymous class. As the name implies, it's an unnamed class. --Unlike a normal class, describe the constructor and the processing part at the same time.

Anonymous class implementation sample


//Interface used in anonymous classes
interface I_Hello {
  public void print();

//Calling class
public class Sample {
	public static void main(String[] args) {

		I_Hello p = new I_Hello() {
			public void print() {
				System.out.println("Hello World");

--Result of execution of anonymous class

Hello World

Sample when implemented without using anonymous class


interface I_Hello {
	public void print();

class Hello implements I_Hello {
	@Override public void print(){
		System.out.println("Hello World");

//Calling class
public class Sample2 {
	public static void main(String[] args) {

		I_Hello p = new Hello();
Hello World

Compare with and without anonymous classes

――As you can see in the sample above, if you do not use an anonymous class, you have to prepare a class Hello that materializes the interface, so it is a large scale compared to an anonymous class. --In the case of anonymous class, it can be described simply.

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