Java Programming Quiz

Which component is responsible to optimize reusable byte code conversion to machine code?

• Class Loader

• Interpreter

• JIT Compiler

• Byte Code Verifier

Predict the output: public static void main(String args[]) { int age; System.out.println(age); }

• 0

• garbage value

• compilation error : variable needs to be initialized before use

• 2147483647

Which of these values can a boolean variable contain?

• true

• false

• 0

• 1

identifiers cannot start with __________

• character

• digit

• _

• $

Predict the output: public class Demo{ public static void main (string args[]){ int a =10,b=9; System.out.println(a

• true

• false

• 10

• 9

public static void main(String args[]){ int i=10; if(i) System.out.println("Hello"); else System.out.println("Bye"); }

• Hello

• Compilation error: incompatible types: int cannot be converted to boolean

• Bye

• runtime error

If an arithmetic expression contains variables of int , byte , and short data types , what will be the data type of its result?

• int

• byte

• float

• short

public static void main(String[] args){ int num1 = 20; double num2 = 0; if(num1 >= 20) num2=1.5; if(num1<30) num2 = 2; System.out.println("Value of num2 is "+ num2); }

• Value of num2 is 2

• Value of num2 is 1.5

• Value of num2 is 2.0

• Value of num2 is 1.50

Can we compare int variable with a Boolean variable?

• True

• False

What is the output of the below Java code snippet?

char ch = 'A';//ASCII 65

int a = ch + 1;

ch = (char)a;

System.out.println(ch);

• A) 66

• B) A

• C) B

• D) 65