gistfile1.java

    /**
     * Substitute sub-strings in side of a string.
     *
     * @param stringBuilder String buffer to use for substitution (buffer is not reset)
     * @param from String to substitute from
     * @param to   String to substitute to
     */
    private static void subst(final StringBuilder stringBuilder, final String from, final String to) {
        int begin = 0, end = 0;

        while ((end = stringBuilder.indexOf(from, end)) != -1) {
            stringBuilder.delete(end, end + from.length());
            stringBuilder.insert(end, to);

            // update positions
            begin = end + to.length();
            end = begin;
        }
    }