Java Basics MCQs: Essential Questions for Exam Preparation

Java is a versatile and widely-used programming language that forms the foundation of many software applications. Whether you’re a beginner or preparing for a Java certification exam, mastering the basics is crucial. In this collection of Java MCQs, we’ve covered fundamental topics such as data types, instance variables, object creation, and key concepts like the final and static keywords. These questions are designed not only to test your knowledge but also to reinforce your understanding of core Java principles.

From understanding default values of variables to correctly implementing object-oriented principles, these MCQs delve into essential areas that are frequently encountered in exams and interviews. By practicing these questions, you will gain a deeper understanding of Java’s syntax, memory management, and control flow mechanisms, all of which are vital for any Java developer.

Use this quiz to solidify your Java basics and prepare effectively for your exams. Each question is accompanied by a detailed explanation, ensuring you grasp the underlying concepts thoroughly. Whether you’re learning Java for the first time or brushing up on your skills, these MCQs will help you succeed.

1. What is the default value of an instance variable of type `int` in Java?
– a) 0
– b) null
– c) -1
– d) 1

2. Which of the following is a valid declaration of a `char` in Java?
– a) `char c = ‘ab’;`
– b) `char c = ‘a’;`
– c) `char c = “a”;`
– d) `char c = 97;`

3. What is the size of a `byte` data type in Java?
– a) 8 bits
– b) 16 bits
– c) 32 bits
– d) 64 bits

4. Which of the following is true about the `final` keyword in Java?
– a) A `final` class can be inherited.
– b) A `final` method cannot be overridden.
– c) A `final` variable can be re-assigned.
– d) `final` and `finally` are the same.

5. How do you correctly create an instance of a class named `MyClass` in Java?
-a) `MyClass obj = MyClass();`
– b) `MyClass obj = new MyClass();`
– c) `MyClass obj = MyClass.new();`
– d) `MyClass obj = new MyClass;`

6. Which of these statements about the `static` keyword is true in Java?
– a) `static` methods can access instance variables directly.
– b) `static` methods belong to the class rather than any object instance.
– c) `static` variables cannot be shared among instances of a class.
– d) A `static` method can be overridden by a non-static method.

7. What will be the output of the following code?
“`java
public class Test {
public static void main(String[] args) {
int x = 5;
System.out.println(x++);
}
}
“`
– a) 4
– b) 5
– c) 6
– d) Compilation error

8. Which of the following is the correct way to declare an array in Java?
– a) `int arr[] = new int(10);`
– b) `int arr[] = new int[10];`
– c) `int arr[10];`
– d) `int arr = new int[10];`

9. What is the purpose of the `break` statement in Java loops?
– a) To skip the current iteration and move to the next one.
– b) To exit from the outer loop.
– c) To exit from the loop entirely.
– d) To jump to a labeled statement outside the loop.

10. In Java, which of these access modifiers provides the most restrictive access?
– a) private
– b) protected
– c) default
– d) public

Answers:

| Question | Answer  |
|————|———–|
| Q.1)          |        a       |
| Q.2)          |       b       |
| Q.3)          |       a       |
| Q.4)          |       b       |
| Q.5)          |       b       |
| Q.6)          |       b       |
| Q.7)          |       b       |
| Q.8)          |       b       |
| Q.9)          |       c       |
| Q.10)        |       a       |