code: public void setTags(String... tags) {
          StringBuilder builder = new StringBuilder();
          boolean first = true;
          for (String s : tags) {
              for (String t : s.split(",")) {
                   t = t.trim();
                   if (!t.isEmpty()) {
                       if (!first) {
                           builder.append(",");
                       }
                       builder.append(t);
                   }
                   first = false;
              }
          }
          // "tags" field must be null for Retrofit to exclude Loggly tags header.
          // Empty header string is not acceptable.
          this.tags = builder.length() > 0 ? builder.toString() : null;
      }
docs: Sets the tags to use for Loggly messages. The list of
  strings are converted into a single CSV (trailing/leading
  spaces stripped from each entry).
  @param tags CSV or list of tags