Makelangelo-software

package com.marginallyclever.util;

/**
 * @author Peter Colapietro
 * @since v7.1.4
 */
public final class UnitTestHelper {

	/**
	 * "If you are not concerned with potential overflow problems this function will
	 * perform about 20-30 times faster than using Integer.parseInt()." ~ Jonas
	 * Klemming
	 *
	 * @param string
	 * @return if the string is an integer. See
	 *         <a href="http://stackoverflow.com/a/237204">What's the best way to
	 *         check to see if a String represents an integer in Java?</a>
	 */
	public static boolean isInteger(String string) {
		if (string == null) {
			return false;
		}
		int length = string.length();
		if (length == 0) {
			return false;
		}
		int i = 0;
		if (string.charAt(0) == '-') {
			if (length == 1) {
				return false;
			}
			i = 1;
		}
		for (; i < length; i++) {
			char c = string.charAt(i);
			if (c <= '/' || c >= ':') {
				return false;
			}
		}
		return true;
	}

	/**
	 * NOOP Constructor.
	 *
	 * @throws IllegalStateException
	 */
	private UnitTestHelper() throws IllegalStateException {
		throw new IllegalStateException();
	}
}