docs: private static void validateProviderDef(final ProviderDef pluginDef) throws PluginException {
  
          if (null == pluginDef.getPluginType() || "".equals(pluginDef.getPluginType())) {
              throw new PluginException("Script plugin missing plugin-type");
          }
          if ("script".equals(pluginDef.getPluginType())) {
              validateScriptProviderDef(pluginDef);
          } else if ("ui".equals(pluginDef.getPluginType())) {
              validateUIProviderDef(pluginDef);
          } else {
              throw new PluginException("Script plugin has invalid plugin-type: " + pluginDef.getPluginType());
          }
      }