public static void quoteHtmlChars(OutputStream output, byte[] buffer, int off, int len)
    throws IOException {
    for (int i = off; i < off + len; i++) {
      switch (buffer[i]) {
        case '&':
          output.write(ampBytes);
          break;
        case '<':
          output.write(ltBytes);
          break;
        case '>':
          output.write(gtBytes);
          break;
        case '\'':
          output.write(aposBytes);
          break;
        case '"':
          output.write(quotBytes);
          break;
        default:
          output.write(buffer, i, 1);
          break;
      }
    }
  }
Quote all of the active HTML characters in the given string as they are added to the buffer.
@param output the stream to write the output to
@param buffer the byte array to take the characters from
@param off    the index of the first byte to quote
@param len    the number of bytes to quote
hbase-http/src/main/java/org/apache/hadoop/hbase/http/HtmlQuoting.java