Package com.google.gerrit.extensions.registration

Class DynamicMap<T>

java.lang.Object
com.google.gerrit.extensions.registration.DynamicMap<T>
All Implemented Interfaces:
Iterable<Extension<T>>
Direct Known Subclasses:
PrivateInternals_DynamicMapImpl
public abstract class DynamicMap<T> extends Object implements Iterable<Extension<T>>
A map of members that can be modified as plugins reload.

Maps index their members by plugin name and export name.

DynamicMaps are always mapped as singletons in Guice. Maps store Providers internally, and resolve the provider to an instance on demand. This enables registrations to decide between singleton and non-singleton members.

  • Method Details

    • mapOf

      public static <T> void mapOf(com.google.inject.Binder binder, Class<T> member)
      Declare a singleton DynamicMap<T> with a binder.

      Maps must be defined in a Guice module before they can be bound: 

       DynamicMap.mapOf(binder(), Interface.class);
 bind(Interface.class)
   .annotatedWith(Exports.named("foo"))
   .to(Impl.class);
      Parameters:
      binder - a new binder created in the module.
      member - type of value in the map.

    • mapOf

      public static <T> void mapOf(com.google.inject.Binder binder, com.google.inject.TypeLiteral<T> member)
      Declare a singleton DynamicMap<T> with a binder.

      Maps must be defined in a Guice module before they can be bound: 

       DynamicMap.mapOf(binder(), new TypeLiteral<Thing<Bar>>(){});
 bind(new TypeLiteral<Thing<Bar>>() {})
   .annotatedWith(Exports.named("foo"))
   .to(Impl.class);
      Parameters:
      binder - a new binder created in the module.
      member - type of value in the map.

    • emptyMap

      public static <T> DynamicMap<T> emptyMap()
      Returns an empty DynamicMap instance *

    • get

      public T get(String pluginName, String exportName) throws com.google.inject.ProvisionException
      Lookup an implementation by name.
      Parameters:
      pluginName - local name of the plugin providing the item.
      exportName - name the plugin exports the item as.
      Returns:
      the implementation. Null if the plugin is not running, or if the plugin does not export this name.
      Throws:
      com.google.inject.ProvisionException - if the registered provider is unable to obtain an instance of the requested implementation.

    • plugins

      public NavigableSet<String> plugins()
      Get the names of all running plugins supplying this type.
      Returns:
      navigatable set of active plugins that supply at least one item.

    • byPlugin

      public NavigableMap<String,com.google.inject.Provider<T>> byPlugin(String pluginName)
      Get the items exported by a single plugin.
      Parameters:
      pluginName - name of the plugin.
      Returns:
      items exported by a plugin, keyed by the export name.

    • iterator

      public Iterator<Extension<T>> iterator()
      Iterate through all entries in an undefined order.
      Specified by:
      iterator in interface Iterable<T>