private boolean isAlpha(char character) {
        // Range of alpha characters in ASCII, should be the same for
        // Unicode according to "The Unicode Standard 4.0", section 5.2
        return (character >= 'A' && character <= 'Z') // Unicode A..Z
                || (character >= 'a' && character <= 'z'); // Unicode a..z
    }
Checks whether a given character is an ASCII alpha or not.
@param character The character to check.
@return <code>true</code> if the character is an ASCII alpha.
src/nu/validator/gnu/xml/aelfred2/SAXDriver.java