Parameter classParam = ext.getParameter(PluginCore.PARAMETER_CLASS);
// extracting plugin class or builder clas
ClassLoader classLoader = this.getPluginManager().getPluginClassLoader(descr);
Class pluginClass = null; // class for the plugin (InferenceAlgorithmOptionPanel)
pluginClass = classLoader.loadClass(classParam.valueAsString());
// intantiating plugin object
InferenceAlgorithmOptionPanel algorithmOptionPanel = null;
algorithmOptionPanel = (InferenceAlgorithmOptionPanel)pluginClass.newInstance();