The Plugin Manager is what your plugin gets sent to after being loaded by the server at startup. The server loads your plugin by finding its main class, annotated by the Plugin annotation that holds its general information, and sends a new instance of it to the manager. The manager then keeps that instance in its own collection that you can look into and pull from using methods provided by itself, thus allowing you to easily interact with another loaded plugin if you so desire.
The PluginManager Class
Public methods inside the PluginManager are used to grab information about the current collection of loaded
plugins, alongside their instances. The plugins are stored inside a PluginContainer (discussed in next
section) to allow for an easy center of information about the specific plugin. As an example, you can use the
PluginManager to communicate with another plugin, grabbing its instance and using the methods it offers to provide
compability or extended features by means of your calling plugin.
Obtaining the Plugin Manager
You can get an instance of the server’s
PluginManager using a few different ways.
1. Dependency Injection
See the Dependency Injection guide for help on using dependency injection.
PluginManager is one of the few API instances that are injected into the main class upon being loaded. To ask
for a reference, create a new variable to hold the
PluginManager instance and simply annotate it with
import com.google.inject.Inject; import org.spongepowered.api.plugin.PluginManager; @Inject private PluginManager pluginManager;
2. The Service Manager
See Services for a full guide about the Service Manager.
The service manager also holds an instance of the server’s
PluginManager. Simply use the method
ServiceManager#provide(Class), passing the
PluginManager‘s class (
PluginManager.class) as a
private PluginManager pluginManager = serviceManager.provide(PluginManager.class);
3. The Game Instance
See the JavaDocs for Game for full information about the class, as well as its methods and their usage.
A game instance can provide a reference to the server’s
PluginManager as well for convenience.
private PluginManager pluginManager = game.getPluginManager();
Now that you have an instance to the plugin manager, let’s use it.
4. Using the Sponge Class
The Sponge class works similarly to
Game, with the exception that since
Sponge contains static
methods. It can be accessed anywhere throughout your plugin. You also do not need to store an instance of it, as you
would need to do with
import org.spongepowered.api.Sponge; private PluginManager pluginManager = Sponge.getPluginManager();
Using the Plugin Manager
The plugin manager provides several methods for working with plugins.
A lot of methods return plugin containers, which will be discussed in the next section. Plugin containers are pretty much self-explanatory “containers” of the actual plugin instance.
With the plugin manager, it is possible to get all plugins currently loaded through the plugin manager:
import org.spongepowered.api.plugin.PluginContainer; import java.util.List; private List<PluginContainer> plugins = pluginManager.getPlugins();
Or, it is possible to obtain an instance to a plugin container directly, by the example shown below:
private PluginContainer myOtherPlugin = pluginManager.getPlugin("myOtherPluginId").orNull();
The PluginContainer Class
When grabbing a plugin from the
PluginManager, you’ll notice very quickly that you are not given an immediate
instance of the requested plugin. Instead, you’ll be greeted by a
PluginContainer containing information about the
plugin attained from its
@Plugin annotation in its main class, as well as the loaded instance.
PluginContainer will hold any generic information about the plugin set by its owning developer. You can use
information from here instead of hard-coding what you know about it in your supporting plugin. An example scenario would
be if the owning developer changes the name of the plugin, references to the latter in the supporting plugin would not
become wrong as a result of this change, provided you’ve used the method PluginContainer#getName() to get
private PluginContainer myOtherPlugin = pluginManager.getPlugin("myOtherPluginId").orNull(); private MyOtherPlugin pluginInstance = (MyOtherPlugin) myOtherPlugin.getInstance();
PluginContainer#getInstance() will return as an
Object. You need to cast it as the target plugin
after obtaining it from the container.