Java syntax

What symbol is used to end a Java statement?

• .

• ;

• :

• !

Answer explanation

Java statements end with a semicolon (;).

How many primitive data types does Java have?

• 6

• 7

• 8

• 9

Answer explanation

Java has 8 primitive data types: byte, short, int, long, float, double, char, and boolean.

What happens if a local int variable is used without initialization?

• It is initialized to 0.

• It retains a garbage value.

• It causes a compilation error.

• It is initialized to -1.

Answer explanation

"Local variables in Java must be explicitly initialized before use, as they do not have default values. Attempting to use an uninitialized local variable results in a compilation error.

What is the size of the 'int' data type in Java?

• 2 bytes

• 4 bytes

• 8 bytes

• 16 bytes

Answer explanation

The 'int' data type in Java occupies 4 bytes (32 bits).

What will this print?
int x = 5; int y = 3; System.out.println(x - y);

• 1

• 2

• 3

• 4

Answer explanation

The difference between x (5) and y (3) is 2.

Identify the error in this code:
int num; System.out.println(num);

• Variable not initialized

• Syntax error in declaration

• Variable out of scope

• Data type mismatch

Answer explanation

Local variables like num must be explicitly initialized before use.

What is the output of this code? System.out.println("Java " + "Programming");

• Java Programming

• Java & Programming

• JavaProgramming

• Programming in Java

Answer explanation

The + operator concatenates the two strings, resulting in Java Programming.

Complete the code to read input from the user: Scanner sc = ____ Scanner(System.in);

• new

• create

• initialize

• import

Answer explanation

The new keyword is required to create an instance of a class.

Predict the output:
int x = 10; System.out.println(x * 2);

• 10

• 15

• 20

• 25

Answer explanation

The variable x is multiplied by 2, resulting in 20.

Complete the statement to declare an integer variable:
____ x = 10;

• int

• float

• char

• String

Answer explanation

The int keyword is used to declare integer variables in Java.