Interfaces
Another way to achieve abstraction in Java, is with interfaces.
An interface is a completely "abstract class" that is used to group related methods with empty bodies:
interface Animal {
public void animalSound(); // interface method (does not have a body)
public void sleep(); // interface method (does not have a body)
}
class Pig implements Animal {
public void animalSound() {
System.out.println("The pig says: wee wee");
}
public void sleep() {
System.out.println("Zzz");
}
}
class Main {
public static void main(String[] args) {
Pig myPig = new Pig();
myPig.animalSound();
myPig.sleep();
}
}