Output of Java program | Set 17

1) What is the output of following program?

public class Test
{
    private static float temp()
    {
        public static float sum = 21;
        return(--(sum));
    }
    public static void main(String[] args)
    {
        Test test = new Test();
        System.out.println(test.temp());
    }
}

a) 21
b) 20
c) Compilation error
d) Runtime error

Ans. (c)
Explanation: static variables are associated with the class and are therefore, not allowed inside a method body.

2) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        int value = 3, sum = 6 + -- value;

        int data = --value + ++value / sum++ * value++ + ++sum  % value--;
        System.out.println(data);
    }
}

a) 1
b) 2
c) 0
d) 3

Ans. (b)
Explanation: Refer to Operator precedence rule in java.

3) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        int temp = 40;
        if(temp == 30 && temp/0 == 4)
        {
            System.out.println(1);
        }
        else
        {
            System.out.println(2);
        }
    }
}

a) 1
b) 2
c) Runtime Exception of java.lang.ArithmeticException
d) Compilation error due to divisibility by 0

Ans. (b)
Explanation: && operator is evaluated from left to right. If the first expression of && operator evaluates to false, then the second operator is not evaluated. There is no compilation error because divide by 0 is a runtime exception.

4) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        int temp = 9;
        int data = 8;
        System.out.println(temp & data);
    }
}

a) 9
b) 8
c) 1000
d) 1001

Ans. (b)
Explanation: & operator is logical bit-wise and operator in java. The and of 9(1001) and 8(1000) is 1000 which is 8.

5) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        int temp = null;
        Integer data = null;
        System.out.println(temp + " " + data);
    }
}

a) null null
b) Compilation error due to temp
c) Compilation error due to data
d) Runtime error

Ans. (b)
Explanation: temp is a primitive data type. Primitive data types cannot be assigned null values. data is an instance of class Integer and therefore can hold null values.