When should you prefer static methods in interfaces and when should you avoid it?

In Java, static methods in interfaces can be useful under certain conditions but should be avoided in others. Here’s when you should prefer them and when you should not.

When to Prefer Static Methods in Interfaces

• Utility Functions: If you need to define utility functions that are related to the interface but do not require access to instance-specific data, static methods can be a good choice.
• Helper Methods: They can serve as helper methods that assist in implementing the interface itself or provide functionality related to the interface.
• Cleaner Code: They can help keep your code cleaner by localizing the functions related to the interface within the interface itself.

When to Avoid Static Methods in Interfaces

• Instance Behavior: If the method needs access to instance data or behavior, you should define it as an instance method instead.
• Inheritance Needs: If you expect subclasses to override the method, it should not be static because static methods cannot be overridden in the same way instance methods can.
• Implementation Flexibility: If you want to provide multiple implementations, static methods limit flexibility as they are bound to the interface and not to an instance.

Example of Static Methods in an Interface

        interface MathOperations {
            static int add(int a, int b) {
                return a + b;
            }
            
            static int multiply(int a, int b) {
                return a * b;
            }
        }
        
        public class Application {
            public static void main(String[] args) {
                int sum = MathOperations.add(5, 10);
                int product = MathOperations.multiply(5, 10);
                
                System.out.println("Sum: " + sum);
                System.out.println("Product: " + product);
            }
        }