code: public @Nonnull
      String getDetailHTML(String key) {
          BugPattern bugPattern = DetectorFactoryCollection.instance().lookupBugPattern(key);
          if (bugPattern == null) {
              return L10N.getLocalString("err.missing_pattern", "Error: missing bug pattern for key") + " " + key;
          }
          return bugPattern.getDetailHTML();
      }
docs: Get an HTML document describing the bug pattern for given key in detail.
  
  @param key
  which HTML details for retrieve