Plugin.java

public interface Plugin extends ResourceLoader, Startable, Stoppable, Lifecycle {

  /**
   * Useful for extension points
   * @return
   */
  List<String> getClassifiers();


  String getContextRoot();

  String resolveFromContext(String... paths);

  Icon getIcon();

  /** @return the plugin registrar */
  PluginRegistrar getRegistrar();

  /** @return the protection domain for this plugin */
  ProtectionDomain getProtectionDomain();

  String getNativeId();

  /** @return the state of this plugin */
  State getState();

  /** Coordinates must be universally unique */

  /**
   * @return all of the extension points this plugin exports. For instance, if this plugin exports a
   *     service-type:
   *     <p>interface SayHello { String sayHello(); } then another plugin can fulfill that extension
   *     point
   */
  List<Class<?>> getExportedExtensionPoints();

  /**
   * This method is effectively the dual of @Plugin#getExportedExtensionPoints
   *
   * @param type
   * @param <T>
   * @return
   */
  <T> T getExtensionPoint(Class<T> type);

  /**
   * @param type
   * @param <T>
   * @return
   */
  <T> boolean exportsExtensionPoint(Class<T> type);

  /** @return the underlying classloader for this plugin */
  ClassLoader getClassLoader();

  /** @return the scratch location for this plugin */
  Path getPluginDirectory();

  /**
   * For plugins that declare a given, configurable extension point, this method allows the plugin
   * framework to instruct that plugin to reconfigure that extension point
   *
   * @param type
   * @param configuration
   */
  void setConfiguration(Class<?> type, Object configuration);

  /**
   * Allow the plugin framework to retrieve a configuration for a given extension point
   *
   * @param type
   * @return
   */
  Object getConfiguration(Class<?> type);

  /**
   * Retrieve all of the configurables for this plugin. An example might be an email-plugin that
   * allows you to configure the email-server, set-from, port, protocol, etc.
   *
   * @return All the configurables exported by this plugin
   */
  List<ConfigurationSet> getConfigurables();

  /**
   * Retrieve all of the configurables under a given category. For instance, if a plugin has a
   * user-component and an admin-component, then you might place all of the administrative
   * configurables under "admin" and all of the user components under "user"
   *
   * @param category
   * @return
   */
  List<ConfigurationSet> getConfigurables(String category);

  /**
   * @return the type of this plugin. If it's top-level, then it may, for instance, generate a
   *     menu-item
   */
  Type getType();

  /**
   * @return the context path of this plugin. For instance, if this plugin is top-level and
   *     generates a menu-item, navigating to that menu-item will display this plugin
   */
  String getContextPath();

  void dispatch(Event event, Event.Mode mode);

  PluginCoordinate getCoordinate();

  /** The plugin state */
  enum State {
    Unknown,
    Running,
    Stopped,
    Failed
  }

  /** */
  enum Type {
    Root,
    Extension
  }
}