code: public void addRepository(String repository) {
  
          // Ignore any of the standard repositories, as they are set up using
          // either addJar or addRepository
          if (repository.startsWith("/WEB-INF/lib")
              || repository.startsWith("/WEB-INF/classes"))
              return;
  
          // Add this repository to our underlying class loader
          try {
              URL url = new URL(repository);
              super.addURL(url);
              hasExternalRepositories = true;
              repositoryURLs = null;
          } catch (MalformedURLException e) {
              IllegalArgumentException iae = new IllegalArgumentException
                  ("Invalid repository: " + repository); 
              iae.initCause(e);
              throw iae;
          }
  
      }
docs: Add a new repository to the set of places this ClassLoader can look for
  classes to be loaded.
  
  @param repository Name of a source of classes to be loaded, such as a
  directory pathname, a JAR file pathname, or a ZIP file pathname
  
  @exception IllegalArgumentException if the specified repository is
  invalid or does not exist