recursive method to detect if a number is a power of 2

isPower2.java

/**
 * @author Robert Boloc
 */

public boolean isPower2(int v) {
        if (v == 1) {
            return true;
        } else if (v % 2 != 0 || v == 0) {
            return false;
        } else {
            return isPower2(v / 2);
        }
    }

This also would work :)

public static boolean isPower2(int number) {
        return number > 0 &&
                (number & (number - 1)) == 0;
    }