@Override
  public void registerFileType(@NotNull FileType type, String @Nullable ... defaultAssociatedExtensions) {
    PluginException.reportDeprecatedUsage("FileTypeManager#registerFileType", "Use `com.intellij.fileType` extension or `FileTypeFactory` instead.");
    List<FileNameMatcher> matchers = new ArrayList<>();
    if (defaultAssociatedExtensions != null) {
      for (String extension : defaultAssociatedExtensions) {
        matchers.add(new ExtensionFileNameMatcher(extension));
      }
    }
    doRegisterFileType(type, matchers);
  }
@Override
  public void registerFileType(@NotNull FileType type, String @Nullable ... defaultAssociatedExtensions)