code: public static String escapeHtml(String s)
    {
      if (s == null)
        return null;
  
      StringBuilder cb = new StringBuilder();
      int lineCharacter = 0;
      boolean startsWithSpace = false;
      
      for (int i = 0; i < s.length(); i++) {
        char ch = s.charAt(i);
  
        lineCharacter++;
        
        if (ch == '<')
          cb.append("&lt;");
        else if (ch == '&')
          cb.append("&amp;");
        else if (ch == '\n' || ch == '\r') {
          lineCharacter = 0;
          cb.append(ch);
          startsWithSpace = false;
        }
        else if (lineCharacter > 70 && ch == ' ' && ! startsWithSpace) {
          lineCharacter = 0;
          cb.append('\n');
          for (; i + 1 < s.length() && s.charAt(i + 1) == ' '; i++) {
          }
        }
        else if (lineCharacter == 1 && (ch == ' ' || ch == '\t')) {
          cb.append((char) ch);
          startsWithSpace = true;
        }
        else
          cb.append(ch);
      }
  
      return cb.toString();
    }
docs: Escapes special symbols in a string.  For example '<' becomes '&lt;'