Java

An anonymous it is an inner class without a name and for which only a single object is created. An anonymous inner class can be useful when making an instance of an object with certain “extras” such as overriding methods of a class or interface, without having to actually subclass a class.

Anonymous inner classes are useful when a class needs to be created and used only once. They are particularly useful for providing implementations of interfaces or abstract classes. They allow for the creation of an object with a single defined behavior without the need to create a separate class.

//Anonymous Inner Class in Java

abstract class testDemo {
    abstract void display();
}

class outerDemo {
    public void outerDisplay() {
        testDemo o = new testDemo() {
            @Override
            public void display() {
                System.out.println("Test Display");
            }
        };
        o.display();
    }
}

public class App {
    public static void main(String[] args) {
        outerDemo o = new outerDemo();
        o.outerDisplay();
    }
}