private boolean isEnabled() {
    OrderEntry entry = myClasspathPanel.getSelectedEntry();
    if (!(entry instanceof ModuleOrderEntry)) return false;

    Module module = ((ModuleOrderEntry)entry).getModule();
    if (module == null) return false;

    ModuleRootModel model = myClasspathPanel.getModuleConfigurationState().getModulesProvider().getRootModel(module);
    return model.getSourceRootUrls().length == 0;
  }
private boolean isEnabled()