chapter 1

Question 1

What is Java?

Answer 1

Java is a high-level, class-based, object-oriented programming language designed to have as few implementation dependencies as possible.

Question 2

True or False: Java is platform-dependent.

Answer 2

False: Java is platform-independent due to the Java Virtual Machine (JVM).

Question 3

What does JVM stand for?

Answer 3

Java Virtual Machine

Question 4

Fill in the blank: Java uses a __________ to manage memory.

Answer 4

Garbage Collector

Question 5

Which of the following is a primitive data type in Java? A) String B) int C) Array

Answer 5

B) int

Question 6

What keyword is used to create a class in Java?

Answer 6

class

Question 7

True or False: In Java, method overloading is allowed.

Answer 7

True

Question 8

What is the default value of a boolean variable in Java?

Answer 8

false

Question 9

Which of the following keywords is used to inherit a class in Java? A) implements B) extends C) inherits

Answer 9

B) extends

Question 10

What is the main method signature in a Java application?

Answer 10

public static void main(String[] args)

Question 11

Fill in the blank: The __________ keyword is used to handle exceptions in Java.

Answer 11

try

Question 12

What is an interface in Java?

Answer 12

An interface is a reference type in Java that is similar to a class and is a collection of abstract methods.

Question 13

True or False: Java supports multiple inheritance through classes.

Answer 13

False: Java does not support multiple inheritance through classes but allows it through interfaces.

Question 14

What is the purpose of the ‘final’ keyword in Java?

Answer 14

The ‘final’ keyword is used to declare constants, prevent method overriding, and inheritance.

Question 15

Which of the following is NOT a feature of Java? A) Automatic garbage collection B) Platform independence C) Pointers

Answer 15

C) Pointers

Question 16

What is the use of the ‘static’ keyword in Java?

Answer 16

‘static’ indicates that a member belongs to the class rather than instances of the class.

Question 17

Fill in the blank: In Java, a __________ is a blueprint from which individual objects are created.

Answer 17

class

Question 18

What does the ‘this’ keyword refer to in Java?

Answer 18

The ‘this’ keyword refers to the current object instance.

Question 19

True or False: In Java, all classes are subclasses of the Object class.

Answer 19

True

Question 20

What is the purpose of the ‘synchronized’ keyword in Java?

Answer 20

‘synchronized’ is used to control access to a block of code or an object by multiple threads.

Question 21

What is a constructor in Java?

Answer 21

A constructor is a special method used to initialize objects.

Question 22

Which of the following collections does not allow duplicate elements? A) List B) Set C) Map

Answer 22

B) Set

Question 23

What is the difference between ‘== ‘ and ‘equals()’ in Java?

Answer 23

’==’ checks for reference equality while ‘equals()’ checks for value equality.

Question 24

What is polymorphism in Java?

Answer 24

Polymorphism allows methods to do different things based on the object it is acting upon.

Question 25

Fill in the blank: The __________ operator is used to create an instance of a class.

Answer 25

new

Question 26

What is the purpose of the 'abstract' keyword in Java?

Answer 26

'abstract' is used to declare a class that cannot be instantiated or a method that must be implemented by subclasses.