Why is a default method needed in an interface?

The method with the default modifier in a Java interface allows defining the implementation of a method directly within the interface. This is useful for:

• Adding new methods to an interface without breaking existing implementations (backward compatibility).
• Providing a base implementation that can be overridden in classes implementing the interface.

Example:

public interface MyInterface {
    void existingMethod();

    default void newDefaultMethod() {
        System.out.println("Default implementation");
    }
}

Classes implementing MyInterface can use newDefaultMethod without needing to implement it.