Tutorials
Courses
Go Premium

Java Polymorphism and Packages

Here are 10 essential multiple-choice questions on Java Polymorphism and Packages, covering key concepts.

Last Updated :

Discuss

Comments

Question 1

What is the key difference between compile-time and runtime polymorphism in Java?

Compile-time polymorphism is implemented using method overriding, while runtime polymorphism is implemented using method overloading.
Compile-time polymorphism is determined during compilation, while runtime polymorphism is resolved at runtime.
Runtime polymorphism is faster than compile-time polymorphism.
Compile-time polymorphism is achieved using interfaces.

Discuss it

Question 2

What will be the output of the following code?

Java

class A {     void display() {         System.out.println("Class A");     } } class B extends A {     void display() {         System.out.println("Class B");     } } public class Main {     public static void main(String[] args) {         A obj = new B();         obj.display();     } }

Class A
Class B
Compilation error
Runtime error

Discuss it

Question 3

Which of the following statements about method overloading is true?

Method overloading occurs only in different classes.
Method overloading is achieved by changing the method name.
Method overloading allows multiple methods with the same name but different parameters.
Overloaded methods must have the same return type.

Discuss it

Question 4

What will be the output of this code?

Java

class Parent {     static void show() {         System.out.println("Parent");     } } class Child extends Parent {     static void show() {         System.out.println("Child");     } } public class Main {     public static void main(String[] args) {         Parent p = new Child();         p.show();     } }

Parent
Child
Compilation error
Runtime error

Discuss it

Question 5

What is the primary use of packages in Java?

To group related classes together.
To speed up Java execution.
To enable multiple inheritance.
To improve memory allocation.

Discuss it

Question 6

What will happen if two classes in different packages have the same name and are imported in a Java file?

Compilation error due to ambiguity.
The last imported class is used.
The first imported class is used.
Java automatically renames one class.

Discuss it

Question 7

Which access modifier allows a member to be accessible within the same package but not from outside?

private
protected
default
public

Discuss it

Question 8

What will be the output of the following program?

Java

package pack1; public class A {     public void display() {         System.out.println("Hello from A");     } }  package pack2; import pack1.A; public class B {     public static void main(String args[]) {         A obj = new A();         obj.display();     } }

Compilation error
Hello from A
Runtime error
No output

Discuss it

Question 9

Which of the following correctly defines method overriding?

Changing the method name while keeping the parameters the same.
Defining a method with the same signature in the child class as in the parent class.
Overriding a static method in the child class.
Changing the return type of a method in a subclass.

Discuss it

Question 10

Which of the following best demonstrates runtime polymorphism in Java?

Calling an overloaded method from the same class
Overriding a method in a subclass and calling it through a superclass reference
Using static methods with the same name in parent and child classes
Accessing private methods from subclasses

Discuss it

Tags:

Java Quiz

There are 10 questions to complete.

Take a part in the ongoing discussion