block.setLength(0);
        prevToken = null;
        while (true) {
            if (ch != -1) {
                ch = readCharFromBuffer();
            }
            if (ch == -1) {
                break;
            } else if (!isDelimiter(ch)) {
                block.append((char) ch);
            } else if (block.length() > 0) {
                break;
            } else {

                buf = new StringBuilder();
            }
        }

        @Override
        public void characters(final char[] ch, final int offset, final int length) {
            if (buf != null) {
                buf.append(new String(ch, offset, length));
            }
        }

        @Override
        public void endElement(final String uri, final String localName, final String qName) {