How to create an abstract class in Java?

One way to create an abstract class in Java is by using the keyword abstract to declare a class as abstract. Abstract classes cannot be instantiated, only inherited, and subclasses must implement the abstract methods defined in the abstract class. Here is an example:

public abstract class Animal {
    private String name;
    
    public Animal(String name) {
        this.name = name;
    }
    
    public abstract void makeSound();
}

In the example above, the class Animal is declared as an abstract class and includes an abstract method makeSound(). Any subclass that inherits from the Animal class must implement the makeSound() method.