private boolean isAstralPrivateUse(int c) {
        return (c >= 0xF0000 && c <= 0xFFFFD)
                || (c >= 0x100000 && c <= 0x10FFFD);
    }
Collect a set of attribues and values from the data part of a PI.

<p>
The bulk of this method and associated methods that follow it here are
copied from the nu.validator.htmlparser.impl.Tokenizer class, with
appropriate modifications.
</p>

@see nu.validator.htmlparser.impl.Tokenizer
@see nu.validator.htmlparser.impl.ErrorReportingTokenizer
src/nu/validator/checker/XmlPiChecker.java