Lesson: 13 | Extending a Class

You can extend a class to provide more specialized behavior. A class that extends another class inherits all the methods and properties of the extended class. The extending class can override the existing virtual methods by using the override keyword in the method definition. Overriding a virtual method allows you to provide a different implementation for an existing method. This means that the behavior of a particular method is different based on the object you’re calling it on.

Apex Class| Rectangle

public virtual class Rectangle {
    public virtual void area() {
        System.debug('The area of a rectangle is the product of its length and width');
    }
}

Apex Class| Square

public class Square extends Rectangle {
    public override void area() {
        System.debug('The area of a square is the product of its base with itself');
    } 
}

Apex Code

Rectangle obj1 = new Rectangle();
obj1.area();

Rectangle obj2 = new Square();
obj2.area();

Exercises

#	Exercise
1	Animal Sound Simulator

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Lesson: 13 | Extending a Class

Apex Class| Rectangle

Apex Class| Square

Apex Code

Execution Log

Considerations

Video

Exercises

Apex Intermediate

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Lesson: 13 | Extending a Class

Apex Class| Rectangle

Apex Intermediate