java.lang.Object | |
↳ | com.google.inject.multibindings.Multibinder<T> |
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) { ... }
}
Contributing 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.
The set's iteration order is consistent with the binding order. This is convenient when multiple elements are contributed by the same module because that module can order its bindings appropriately. Avoid relying on the iteration order of elements contributed by different modules, since there is no equivalent mechanism to order modules.
The set is unmodifiable. Elements can only be added to the set by configuring the multibinder. Elements can never be removed from the set.
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.
Public Methods | |||||||||||
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Returns a binding builder used to add a new element in the set.
| |||||||||||
Returns a new multibinder that collects instances of
type in a Set that is
itself bound with no binding annotation. | |||||||||||
Returns a new multibinder that collects instances of
type in a Set that is
itself bound with annotationType . | |||||||||||
Returns a new multibinder that collects instances of
type in a Set that is
itself bound with annotation . | |||||||||||
Returns a new multibinder that collects instances of
type in a Set that is
itself bound with no binding annotation. | |||||||||||
Returns a new multibinder that collects instances of
type in a Set that is
itself bound with annotationType . | |||||||||||
Returns a new multibinder that collects instances of
type in a Set that is
itself bound with annotation . | |||||||||||
Configures the bound set to silently discard duplicate elements.
|
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Inherited Methods | |||||||||||
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From class
java.lang.Object
|
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.
Returns a new multibinder that collects instances of type
in a Set that is
itself bound with no binding annotation.
Returns a new multibinder that collects instances of type
in a Set that is
itself bound with annotationType
.
Returns a new multibinder that collects instances of type
in a Set that is
itself bound with annotation
.
Returns a new multibinder that collects instances of type
in a Set that is
itself bound with no binding annotation.
Returns a new multibinder that collects instances of type
in a Set that is
itself bound with annotationType
.
Returns a new multibinder that collects instances of type
in a Set that is
itself bound with annotation
.
Configures the bound set to silently discard duplicate elements. When multiple equal values are bound, the one that gets included is arbitrary. When multiple modules contribute elements to the set, this configuration option impacts all of them.