dagger

Annotation Type Multibindings

@Documented
 @Target(value=TYPE)
 @Beta
public @interface Multibindings

Annotates interfaces that declare multibindings.

You can declare that a multibound set or map is bound by nesting a @Multibindings-annotated interface within a module, with methods that return the sets or maps you want to declare.

You do not have to use @Multibindings for sets or maps that have at least one contribution, but you do have to declare them if they may be empty.

  @Module
 class MyModule {
    @Multibindings
   interface MyMultibindings {
      Set<Foo> aSet();
      @MyQualifier Set<Foo> aQualifiedSet();
      Map<String, Foo> aMap();
      @MyQualifier Map<String, Foo> aQualifiedMap();
   }

    @Provides
   static Object usesMultibindings(
        Set<Foo> set,  @MyQualifier Map<String, Foo> map) {
     return …
   }
 }
 

All methods on the interface and any supertypes (except for methods on Object) are used to declare multibindings. The names of the interface and its methods are ignored. A given set or map multibinding can be declared any number of times without error. Dagger never implements the interface or calls any of its methods.

See Also:

Multibindings