void characters(char[] ch, int start, int length) {
        int newBufferLength = bufferLength + length;
        if (offset + newBufferLength > buffer.length) {
            char[] newBuf = new char[((newBufferLength >> 11) + 1) << 11];
            System.arraycopy(buffer, offset, newBuf, 0, bufferLength);
            buffer = newBuf;
            offset = 0;
        }
        System.arraycopy(ch, start, buffer, offset + bufferLength, length);
        bufferLength = newBufferLength;
    }
@see java.lang.StringBuffer#append(char[], int, int)
@see org.xml.sax.ContentHandler#characters(char[], int, int)
src/nu/validator/source/Line.java