Class Multibinder<T>

  • Direct Known Subclasses:
    Multibinder.RealMultibinder

    public abstract class Multibinder<T>
    extends java.lang.Object
    An API to bind multiple values separately, only to later inject them as a complete collection. Multibinder is intended for use in your application's module:
    
     public class SnacksModule extends AbstractModule {
       protected void configure() {
         Multibinder<Snack> multibinder
             = Multibinder.newSetBinder(binder(), Snack.class);
         multibinder.addBinding().toInstance(new Twix());
         multibinder.addBinding().toProvider(SnickersProvider.class);
         multibinder.addBinding().to(Skittles.class);
       }
     }

    With this binding, a Set<Snack> can now be injected:

    
     class SnackMachine {
       @Inject
       public SnackMachine(Set<Snack> snacks) { ... }
     }

    Create multibindings from different modules is supported. For example, it is okay to have both CandyModule and ChipsModule to both create their own Multibinder<Snack>, and to each contribute bindings to the set of snacks. When that set is injected, it will contain elements from both modules.

    Elements are resolved at set injection time. If an element is bound to a provider, that provider's get method will be called each time the set is injected (unless the binding is also scoped).

    Annotations are be used to create different sets of the same element type. Each distinct annotation gets its own independent collection of elements.

    Elements must be distinct. If multiple bound elements have the same value, set injection will fail.

    Elements must be non-null. If any set element is null, set injection will fail.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  Multibinder.RealMultibinder<T>
      The actual multibinder plays several roles:
    • Method Summary

      All Methods Static Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      abstract LinkedBindingBuilder<T> addBinding()
      Returns a binding builder used to add a new element in the set.
      static <T> Multibinder<T> newSetBinder​(Binder binder, java.lang.Class<T> type)
      Returns a new multibinder that collects instances of type in a Set that is itself bound with no binding annotation.
      static <T> Multibinder<T> newSetBinder​(Binder binder, java.lang.Class<T> type, java.lang.annotation.Annotation annotation)
      Returns a new multibinder that collects instances of type in a Set that is itself bound with annotation.
      static <T> Multibinder<T> newSetBinder​(Binder binder, java.lang.Class<T> type, java.lang.Class<? extends java.lang.annotation.Annotation> annotationType)
      Returns a new multibinder that collects instances of type in a Set that is itself bound with annotationType.
      static <T> Multibinder<T> newSetBinder​(Binder binder, TypeLiteral<T> type)
      Returns a new multibinder that collects instances of type in a Set that is itself bound with no binding annotation.
      static <T> Multibinder<T> newSetBinder​(Binder binder, TypeLiteral<T> type, java.lang.annotation.Annotation annotation)
      Returns a new multibinder that collects instances of type in a Set that is itself bound with annotation.
      static <T> Multibinder<T> newSetBinder​(Binder binder, TypeLiteral<T> type, java.lang.Class<? extends java.lang.annotation.Annotation> annotationType)
      Returns a new multibinder that collects instances of type in a Set that is itself bound with annotationType.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Method Detail

      • newSetBinder

        public static <T> Multibinder<T> newSetBinder​(Binder binder,
                                                      TypeLiteral<T> type)
        Returns a new multibinder that collects instances of type in a Set that is itself bound with no binding annotation.
      • newSetBinder

        public static <T> Multibinder<T> newSetBinder​(Binder binder,
                                                      java.lang.Class<T> type)
        Returns a new multibinder that collects instances of type in a Set that is itself bound with no binding annotation.
      • newSetBinder

        public static <T> Multibinder<T> newSetBinder​(Binder binder,
                                                      TypeLiteral<T> type,
                                                      java.lang.annotation.Annotation annotation)
        Returns a new multibinder that collects instances of type in a Set that is itself bound with annotation.
      • newSetBinder

        public static <T> Multibinder<T> newSetBinder​(Binder binder,
                                                      java.lang.Class<T> type,
                                                      java.lang.annotation.Annotation annotation)
        Returns a new multibinder that collects instances of type in a Set that is itself bound with annotation.
      • newSetBinder

        public static <T> Multibinder<T> newSetBinder​(Binder binder,
                                                      TypeLiteral<T> type,
                                                      java.lang.Class<? extends java.lang.annotation.Annotation> annotationType)
        Returns a new multibinder that collects instances of type in a Set that is itself bound with annotationType.
      • newSetBinder

        public static <T> Multibinder<T> newSetBinder​(Binder binder,
                                                      java.lang.Class<T> type,
                                                      java.lang.Class<? extends java.lang.annotation.Annotation> annotationType)
        Returns a new multibinder that collects instances of type in a Set that is itself bound with annotationType.
      • addBinding

        public abstract LinkedBindingBuilder<T> addBinding()
        Returns a binding builder used to add a new element in the set. Each bound element must have a distinct value. Bound providers will be evaluated each time the set is injected.

        It is an error to call this method without also calling one of the to methods on the returned binding builder.

        Scoping elements independently is supported. Use the in method to specify a binding scope.