Simple GCD utility in Java

I previously discussed the performance concerns about different GCD algorithms. I wrote a simple Java class that implements the Binary GCD algorithm. It is a really tiny class that has only two easy-to-use methods. See for yourself:

GCD.java

package math;

/**
 * This is a utility class that provides the functionality of calculating the
 * GCD or Greatest Common Divisor (also known as HCF or Highest Common
 * Factor) of two or more integers.
 * 
 * It has only two methods:
 * 
 * {@link #of(long, long)}
 * {@link #of(long, long, long...)}
 * 
 * Usage is very simple:
 * 
 * ...
 * // assuming a, b, c, d and e are integers (long, int, etc.)
 * long gcd1 = GCD.of(a, b);
 * long gcd2 = GCD.of(a, b, c);
 * long gcd3 = GCD.of(a, b, c, d);
 * long gcd4 = GCD.of(a, b, c, e);
 * ...
 *

*
* @author Subhomoy Haldar
* @version 1.0
*/
public class GCD {

/**
* Private constructor to prevent instantiation.
*/
private GCD() {
throw new Error("Instantiation not allowed.");
}

/**
* This method computes the GCD of two positive integers using the Binary
* GCD algorithm.
*

* This method does not complain if the integers provided are negative.
* In such a case, it simply the absolute value and performs the
* computation. If one of the arguments is zero, the other argument is
* returned. If both are zero, then zero is returned.
*
* @param a The first positive integer.
* @param b The second positive integer.
* @return The GCD of two positive integers.
*/
public static long of(long a, long b) {
// corner cases
if (a == 0) return b;
if (b == 0) return a;
if (a >>= a0;
b >>>= b0;
while (a != b) {
if (a > b) {
a -= b;
a >>>= Long.numberOfTrailingZeros(a);
} else {
b -= a;
b >>>= Long.numberOfTrailingZeros(b);
}
}
ret

Instead of throwing an Error, an AssertionError would be better.
An Error is too broad.
An AssertionError conveys better that instantiating is an error by the programmer, violating a precondition.
(The only way this error will be triggered is if you try to create an instance within this class.)

private GCD() {
    throw new AssertionError("Instantiation not allowed.");
}

As this class has only private constructors,
it cannot be extended:
derived classes would need to call a constructor in the super-class,
but none are available.
To make the intention perfectly clear that this class is not designed to be extended, it's good to make it final.

StackExchange Code Review Q#107809, answer score: 6