code: @Override
      public void stopPlugins() {
          // stop started plugins in reverse order
          Collections.reverse(startedPlugins);
          Iterator<PluginWrapper> itr = startedPlugins.iterator();
          while (itr.hasNext()) {
              PluginWrapper pluginWrapper = itr.next();
              PluginState pluginState = pluginWrapper.getPluginState();
              if (PluginState.STARTED == pluginState) {
                  try {
                      log.info("Stop plugin '{}'", getPluginLabel(pluginWrapper.getDescriptor()));
                      pluginWrapper.getPlugin().stop();
                      pluginWrapper.setPluginState(PluginState.STOPPED);
                      itr.remove();
  
                      firePluginStateEvent(new PluginStateEvent(this, pluginWrapper, pluginState));
                  } catch (PluginException e) {
                      log.error(e.getMessage(), e);
                  }
              }
          }
      }
docs: Stop all active plugins.