private boolean tryWhitespace() throws SAXException, IOException {
        char c;
        c = readCh();
        if (isWhitespace(c)) {
            skipWhitespace();
            return true;
        } else {
            unread(c);
            return false;
        }
    }
Return true if we can read some whitespace.
<p>
This is simply a convenience method.
<p>
This method will push back a character rather than an array whenever
possible (probably the majority of cases).

@return true if whitespace was found.
src/nu/validator/gnu/xml/aelfred2/XmlParser.java