Private data members in Java - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a private integer variable named age.

Java

class Person {
    [1] int age;
}

Drag options to blanks, or click blank then click option'

Astatic

Bprivate

Cprotected

Dpublic

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'public' instead of 'private' allows access from anywhere.

Using 'static' changes the variable to belong to the class, not an instance.

The keyword private makes the variable accessible only within the class.

2fill in blank

medium

Complete the code to create a private String variable called name.

Java

class Student {
    [1] String name;
}

Drag options to blanks, or click blank then click option'

Apublic

Bfinal

Cprivate

Dprotected

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'public' exposes the variable to all classes.

Using 'final' makes the variable constant but does not restrict access.

Use private to keep the variable accessible only inside the class.

3fill in blank

hard

Fix the error in the code by choosing the correct access modifier for the data member.

Java

class Car {
    [1] String model;
}

Drag options to blanks, or click blank then click option'

Aprivate

Bpublic

Cstatic

Dfinal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'public' exposes the variable to all classes.

Using 'static' or 'final' does not control access.

The data member should be private to follow encapsulation principles.

4fill in blank

hard

Fill both blanks to declare two private data members: an int id and a String name.

Java

class Employee {
    [1] int id;
    [2] String name;
}

Drag options to blanks, or click blank then click option'

Aprivate

Bpublic

Cprotected

Dstatic

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing access modifiers can cause inconsistent access.

Using 'public' exposes the variables.

Both variables should be declared private to keep them hidden from outside access.

5fill in blank

hard

Fill all three blanks to declare private data members: a String title, an int pages, and a double price.

Java

class Book {
    [1] String title;
    [2] int pages;
    [3] double price;
}

Drag options to blanks, or click blank then click option'

Apublic

Bprivate

Cprotected

Dfinal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'public' or 'protected' exposes the data members.

Using 'final' only makes variables constant but does not restrict access.

All three data members should be private to protect the data inside the class.