Interface vs Abstract Class in Java: Key Differences Explained

In Java, both interfaces and abstract classes are used to define abstract methods. However, there are key differences between them. An interface defines a contract that classes must follow, whereas an abstract class provides a partial implementation. Interfaces use the `interface` keyword, while abstract classes use the `abstract` keyword.

Here’s an example of an interface and an abstract class:

interface Animal {
    void sound();
}

abstract class Bird {
    abstract void fly();
    void eat() {
        System.out.println("Bird is eating");
    }
}
            

In this example, the interface `Animal` defines a method without implementation, while the abstract class `Bird` provides both an abstract and a concrete method. Understanding when to use an interface or an abstract class is important for designing flexible and reusable Java programs.