@NonNull
        @Override
        public Appendable append(@Nullable final CharSequence csq, final int start, final int end) {
            if (csq != null) {
                final int len = textBuilder.length();
                for (int i = start; i < end; i++) {
                    scan(csq.charAt(i), len + i);
                }
            }
            textBuilder.append(csq, start, end);
            return this;
        }
Appender which scans and tokenizes certain HTML tokens (for later formatting)
main/src/main/java/cgeo/geocaching/utils/html/HtmlUtils.java