code: public List getPlugins(final Class pluginClass) {
          synchronized (pluginMap) {
              List pluginList = new ArrayList(pluginMap.size());
              Iterator iter = pluginMap.values().iterator();
  
              while (iter.hasNext()) {
                  Object plugin = iter.next();
  
                  if (pluginClass.isInstance(plugin)) {
                      pluginList.add(plugin);
                  }
              }
              return pluginList;
          }
      }
docs: Returns all the plugins for a given repository that are instances
  of a certain class.
  
  @param pluginClass the class the plugin must implement to be selected.
  @return List list of plugins from the repository.