1Z0-819 Java Fundamentals & Object-Oriented Programming

Question 1

What is the main purpose of the Java Virtual Machine (JVM)?

Accepted Answer

To convert Java bytecode to machine code at runtime

Answer

To compile Java source code.

Answer

To write Java programs.

Answer

To store Java libraries.

Question 2

Which keyword is used to create a subclass in Java?

Accepted Answer

extends

Answer

inherits

Answer

instanceof

Answer

super

Question 3

What is encapsulation in object-oriented programming?

Accepted Answer

Using private fields with public getters/setters

Answer

Exposing all class variables directly.

Answer

Avoiding methods in a class.

Answer

Extending multiple classes.

Question 4

What does the 'static' keyword denote in Java?

Accepted Answer

Class-level access without needing an object

Answer

Instance-level access.

Answer

A method that returns null.

Answer

A variable that cannot be changed.

Question 5

Which of the following is not a Java access modifier?

Accepted Answer

Answer

public

Answer

protected

Answer

friendly

Answer

private

Question 6

What is polymorphism in Java?

Accepted Answer

One interface, many implementations

Answer

Using multiple classes in one file.

Answer

Compiling code to multiple platforms.

Answer

Writing code with multiple threads.

Question 7

What is the result of using 'final' with a variable in Java?

Accepted Answer

The variable is assigned only once

Answer

The variable is deleted.

Answer

The variable can be changed later.

Answer

The variable becomes static.

Question 8

What is inheritance in Java?

Accepted Answer

Allowing a class to reuse another class's code via 'extends'

Answer

Copying code between classes.

Answer

Running multiple classes simultaneously.

Answer

Preventing method reuse.

Question 9

Which interface must be implemented to sort objects in Java?

Accepted Answer

Comparable

Answer

Serializable

Answer

Runnable

Answer

Cloneable