code: @Override
      public boolean transform(IResource resource) throws Exception {
          String path = resource.getSourcePath();
          
          if (path.startsWith("META-INF/")) {
              return false;
          }
          
          if (hsFile == null && loader.isHelpSetFile(path)) {
              hsFile = getResourceBase() + resource.getTargetPath();
          }
          
          return super.transform(resource);
      }
docs: Excludes resources under the META-INF folder and checks the resource against the help set
  pattern, saving a path reference if it matches.