Java mimic of PHP's ucfirst function

ucfirst.java

/**
 * Mimics PHP's ucfirst function.
 *
 * @param  subject The string to be ucfirst'd
 * @return The subject string with an uppercased first character
 */
final public static String ucfirst(String subject)
{
    return Character.toUpperCase(subject.charAt(0)) + subject.substring(1);
}

Error if subect is empty