code: private static void addMimeGroups(String... groups) {
          for (String mimeType : EXTENSIONS.values()) {
              for (String group : groups) {
                  if (mimeType.startsWith(group) && !COMPRESSED_MIME.contains(mimeType)) {
                      COMPRESSED_MIME.add(mimeType);
                  }
              }
          }
      }
docs: Adds a group to the compressed list.
  
  @param groups the groups