Java Guava | isPowerOfTwo(long x) of LongMath Class with Examples

The method isPowerOfTwo(long x) of Guava’s LongMath Class is used to check if a number is power of two or not. It accepts the number to be checked as a parameter and return boolean value true or false based on whether the number is a power of 2 or not.

Syntax:

public static boolean isPowerOfTwo(long x)

Parameter: This method accepts a single parameter x which is of long type which is to be checked for power of two.

Return Value: This method returns a boolean value. It returns true if x represents power of 2 and false if x doesn’t represent power of 2.

Exceptions: The method doesn’t throw any exception.

Note: This differs from Long.bitCount(x) == 1, because Long.bitCount(Long.MIN_VALUE) == 1, but Long.MIN_VALUE is not a power of two.

Example 1 :

// Java code to show implementation of
// isPowerOfTwo(long x) method of Guava's
// LongMath class

import java.math.RoundingMode;
import com.google.common.math.LongMath;

class GFG {

    // Driver code
    public static void main(String args[])
    {
        long n1 = 52;

        // Using isPowerOfTwo(long x) method
        // of Guava's LongMath class
        if (LongMath.isPowerOfTwo(n1))
            System.out.println(n1
                               + " is power of 2");
        else
            System.out.println(n1
                               + " is not power of 2");

        long n2 = 4;

        // Using isPowerOfTwo(long x) method
        // of Guava's LongMath class
        if (LongMath.isPowerOfTwo(n2))
            System.out.println(n2
                               + " is power of 2");
        else
            System.out.println(n2
                               + " is not power of 2");
    }
}

Output:

52 is not power of 2
4 is power of 2

Example 2:

// Java code to show implementation of
// isPowerOfTwo(long x) method of Guava's
// LongMath class

import java.math.RoundingMode;
import com.google.common.math.LongMath;

class GFG {

    // Driver code
    public static void main(String args[])
    {
        long n1 = 256;

        // Using isPowerOfTwo(long x) method
        // of Guava's LongMath class
        if (LongMath.isPowerOfTwo(n1))
            System.out.println(n1
                               + " is power of 2");
        else
            System.out.println(n1
                               + " is not power of 2");

        long n2 = 4096;

        // Using isPowerOfTwo(long x) method
        // of Guava's LongMath class
        if (LongMath.isPowerOfTwo(n2))
            System.out.println(n2
                               + " is power of 2");
        else
            System.out.println(n2
                               + " is not power of 2");
    }
}

Output:

256 is power of 2
4096 is power of 2

Reference: https://google.github.io/guava/releases/20.0/api/docs/com/google/common/math/LongMath.html#isPowerOfTwo-long-