Quiz Discussion

With x = 0, which of the following are legal lines of Java code for changing the value of x to 1?

   1. x++;
   2. x = x + 1;
   3. x += 1;
   4. x =+ 1;

• 1]

  1, 2 & 3

• 2]

  1 & 4

• 3]

  1, 2, 3 & 4

• 4]

  3 & 2

What will be the output of the following Java code?

    class operators 
    {
        public static void main(String args[])
        {
            int var1 = 5; 
            int var2 = 6;
            int var3;
            var3 = ++ var2 * var1 / var2 + var2;
            System.out.print(var3);
        } 
    }

• 1]

  10

• 2]

  11

• 3]

  12

• 4]

  56

Can 8 byte long data type be automatically type cast to 4 byte float data type?

• 1]

  true

• 2]

  false

Which operator is used to invert all the digits in a binary representation of a number?

• 1]

  ~

• 2]

  <<<

• 3]

  >>>

• 4]

  ^

Which of these is not a bitwise operator?

• 1]

  &

• 2]

  &=

• 3]

  |=

• 4]

  <=

Decrement operator, −−, decreases the value of variable by what number?

• 1]

  1

• 2]

  2

• 3]

  3

• 4]

  4

What will be the output of the following Java code?

    class Output 
    {
        public static void main(String args[]) 
        {    
             boolean a = true;
             boolean b = false;
             boolean c = a ^ b;
             System.out.println(!c);
        } 
    }

• 1]

  0

• 2]

  1

• 3]

  true

• 4]

  false

What should be expression1 evaluate to in using ternary operator as in this line?

 expression1 ?  expression2  :  expression3

• 1]

  Integer

• 2]

  Floating – point numbers

• 3]

  Boolean

• 4]

  None of the mentioned

Which of these statements are incorrect?

• 1]

  Assignment operators are more efficiently implemented by Java run-time system than their equivalent long forms

• 2]

  Assignment operators run faster than their equivalent long forms

• 3]

  Assignment operators can be used only with numeric and character data type

• 4]

  None of the mentioned

What is the order of precedence (highest to lowest) of following operators?

    1. &    
    2. ^
    3. ?:

• 1]

  1 -> 2 -> 3

• 2]

  2 -> 1 -> 3

• 3]

  3 -> 2 -> 1

• 4]

  2 -> 3 -> 1