What are some examples of abstract classes in Java?

Can you explain what an abstract class is in Java?

An abstract class in Java is a class that cannot be instantiated and is meant to be subclassed. It can have abstract methods (without implementation) and concrete methods (with implementation).

What are some examples of abstract classes in Java?

Some examples of abstract classes in Java include:

1. Animal - an abstract class with methods like makeSound().
2. Shape - an abstract class with methods like draw() and area().
3. Vehicle - an abstract class with methods like start() and stop().

How do I implement an abstract class in my code?

To implement an abstract class, you need to create a subclass that extends the abstract class and provides implementations for its abstract methods. For example:

abstract class Animal {
    abstract void makeSound();
}
class Dog extends Animal {
    void makeSound() {
        System.out.println("Bark");
    }
}