why do we need abstract classes in Java? [closed]

Answer 1

The are many uses of abstract clasees, the main purpose of abstract classes is to function as base classes which can be extended by subclasses to create a full implementation.

For example,

You may have three steps to be implemented in your program,

• Few steps before the action
• Some action to be performed
• Few steps after the action

So in this case you can define an abstract class with the three methods like this:

public abstract MyAbstractProcess {
    public void stepBefore() {
        //implementation directly in abstract superclass
    }

    public abstract void action(); // implemented by subclasses

    public void stepAfter() {
        //implementation directly in abstract superclass
    }
}

Also, the above example of abstract class Animal is also a very good example.