Page 67 - Viva ICSE Computer Studies 8 : E-book

properties are inherited is known as parent class. It helps to reuse the code and establish a
relationship between diff erent classes. Inheritance allows to enlarge the functionality of a class
which already exists. You make a class that uses the attributes and behavior of another class.
It doesn’t mean that the new class only acquires the attributes of the existing class but it
consists of a few new attributes and behaviors that are specifi c to the class.
ABILITIES
INHERITED SKILLS
• Cook
NEW SKILLS
• Sing
• Dance
• Teach

ABILITIES ABILITIES ABILITIES
• Cook • Cook • Cook
• Sing • Sing • Sing
• Dance • Dance • Dance
• Teach • Teach • Teach
• Fly Planes • Code • Shoot Guns
• Play Football • Repair Electronics

Polymorphism

Polymorphism is obtained from two Latin words: poly and morph. Poly means many and morph
means forms. Anything can be called polymorph when it is present in more than one form.
Now let’s understand the concept with an example. Suppose, you are in a classroom, at that
time you will behave like a student, when you are in market, you will behave like a customer,
when you at your home you will behave like a son or daughter. Here, one person presents
varied behaviors. Hence, he exhibits polymorphism.

Starting BlueJ
Step 2
Follow these steps to start BlueJ.
1. Click on the Start button.

2. Click on the BlueJ option in the menu.
A ‘BlueJ’ screen appears, followed by BlueJ
working environment screen.

Step 1

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