OOP Java Basics

What is Java bytecode?

• Machine code for Java applications

• A compiled version of Java that runs on the JVM

• A scripting language used by Java

• The high-level Java source code

Which of the following is not a primitive data type?

• int

• float

• String

• boolean

What is the size of a byte in Java?

• 4 bits

• 8 bits

• 16 bits

• 32 bits

Which of the following is true about Java arrays?

• Arrays can hold only objects

• Arrays have a dynamic size by default

• Arrays store elements of the same data type

• Arrays do not allow duplicate values

What is the default value of an uninitialized int variable in a Java class?

• 0

• null

• undefined

• -1

What does the Java compiler "javac" do?

• Translates Java code into machine code

• Converts Java source code into bytecode

• Runs Java programs

• Converts bytecode into machine code

What is the output of System.out.println(10 / 5)?

• 2.5

• 2

• 2.0

• 2.25

Which loop is best suited when the number of iterations is known beforehand?

• while loop

• do while loop

• for loop

• infinite loop

What will happen if a class does not have a main method?

• The program will run normally

• The program will throw a runtime error

• The program will not compile

• The program will execute partially

What is JVM in Java?

• Java Virtual Machine

• Java Variable Model

• Java Visual Maker

• Java Version Manager