What are some examples of interfaces in Java?

What are some examples of interfaces in Java?

In Java, an interface is a reference type, similar to a class, that can contain only constants, method signatures, default methods, static methods, and nested types. Here are a few examples:

1. Comparable: This interface is used to compare objects.
2. Runnable: This interface is used to execute code in a separate thread.
3. List: This interface represents an ordered collection of elements.

Can you explain the Comparable interface?

Sure! The Comparable interface is used to define a natural ordering for objects of a class. It has a single method, compareTo(T o), which compares the current object with the specified object. Classes that implement this interface can be sorted using collections like Collections.sort().

What about the Runnable interface?

The Runnable interface is designed for classes whose instances are intended to be executed by a thread. It has a single method, run(), which contains the code that should be executed when the thread is started. You can implement this interface and pass it to a Thread object.

Can you give an example of a custom interface?

Certainly! Here's a simple example of a custom interface:

public interface Animal {
    void makeSound();
}

Classes like Dog and Cat can implement this interface and provide their own implementation of the makeSound() method.