Reverse actual bits of the given number in java

Java program for Reverse actual bits of the given number. Here more information.

/*
  Java program for
  Reverse the bits of a number
*/
public class InvertBits
{
    // Reverse the bits element of a number
    public void reverseBits(int num)
    {

        int result = 0;
        // Assume num is positive integer
        int n = num;
        // Execute loop until, when the n is not zero
        while (n != 0)
        {
            if (result != 0)
            {
                result = result << 1;
            }
            if ((n & 1) == 1)
            {
                // When first bit is active
                result = result ^ 1;
            }
            n = n / 2;
        }
        // Display given number
        System.out.println("\n Number : " + num);
        // After the reversing bits
        System.out.println(" Output : " + result);
    }
    public static void main(String[] args)
    {
        InvertBits task = new InvertBits();
        // Test cases
        // ---------------
        // num = 16
        // 10000 => 00001 (1)
        task.reverseBits(16);
        // num = 35
        // 100011 => 110001 (49)
        task.reverseBits(35);
        // num = 20  
        // 10100  => 00101 (5)
        task.reverseBits(20);

    }
}

Output

 Number : 16
 Output : 1

 Number : 35
 Output : 49

 Number : 20
 Output : 5