Java Programming Quiz

What is Java primarily known for?

• Being a low-level programming language

• Platform independence

• Being a scripting language

• High memory consumption

Answer explanation

Java is primarily known for its platform independence, allowing code to run on any device with a Java Virtual Machine (JVM). This feature contrasts with low-level and scripting languages, which do not offer the same level of portability.

Which of the following is a characteristic of Java?

• Automatic memory management

• Direct memory access

• No support for multithreading

• No garbage collection

Answer explanation

Java is known for its automatic memory management, which includes garbage collection. This feature helps prevent memory leaks and simplifies memory handling for developers, making it a key characteristic of the language.

What does JVM stand for?

• Java Virtual Machine

• Java Variable Machine

• Java Version Machine

• Java Visual Machine

Answer explanation

JVM stands for Java Virtual Machine, which is an engine that provides a runtime environment to execute Java bytecode. The other options do not accurately describe this essential component of Java technology.

Which of the following is NOT a type of constructor in Java?

• No-Arg Constructor

• Static Constructor

• Parameterized Constructor

• Default Constructor

Answer explanation

In Java, constructors include No-Arg, Parameterized, and Default Constructors. However, there is no such thing as a Static Constructor, making it the correct answer as the type that does not exist.

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

• To refer to the parent class

• To refer to the current object

• To create a new instance

• To access static methods

Answer explanation

The 'this' keyword in Java is used to refer to the current object within a class. It helps distinguish between instance variables and parameters when they have the same name, ensuring clarity in the code.

Which of the following statements about Java classes is true?

• A class cannot have fields

• A class is a blueprint for creating objects

• A class can have multiple constructors with the same signature

• A class can only have one method

Answer explanation

The correct statement is that a class is a blueprint for creating objects. This means classes define the structure and behavior of objects in Java. The other options are incorrect as classes can have fields, multiple constructors with different signatures, and more than one method.

What is the output of the following code: System.out.println(5 + 5);?

• 10

• 50

• 55

• Error

Answer explanation

The code performs addition. 5 + 5 equals 10, which is printed to the console. Therefore, the correct answer is 10.

Which of the following is a valid way to create an object in Java?

• new ClassName objectName;

• objectName = new ClassName();

• ClassName objectName = ClassName();

• ClassName objectName = new ClassName();

Answer explanation

The correct way to create an object in Java is 'ClassName objectName = new ClassName();'. This syntax declares a variable and initializes it with a new instance of the class. The other options are incorrect.

What is the role of the Java Development Kit (JDK)?

• To develop Java applications

• To run Java applications

• To compile Java applications only

• To manage Java memory

Answer explanation

The Java Development Kit (JDK) is essential for developing Java applications as it includes tools for writing, compiling, and debugging code. While it can compile Java applications, its primary role is to facilitate the entire development process.

What does the 'finalize()' method do in Java?

• It is called by the garbage collector

• It initializes an object

• It terminates the program

• It creates a new object

Answer explanation

The 'finalize()' method in Java is called by the garbage collector before an object is reclaimed, allowing it to perform cleanup operations. It does not initialize, terminate the program, or create new objects.