Package com.google.inject.spi

Class ProviderLookup<T>

  • All Implemented Interfaces:
    Element
    public final class ProviderLookup<T>
extends Object
implements Element
    A lookup of the provider for a type. Lookups are created explicitly in a module using getProvider() statements: 
         Provider<PaymentService> paymentServiceProvider
         = getProvider(PaymentService.class);
    Since:
    2.0
    Author:
    jessewilson@google.com (Jesse Wilson)

    • Constructor Detail

      • ProviderLookup

        public ProviderLookup​(Object source,
                      Key<T> key)

      • ProviderLookup

        public ProviderLookup​(Object source,
                      Dependency<T> dependency)
        Since:
        4.0

    • Method Detail

      • getSource

        public Object getSource()
        Description copied from interface: Element
        Returns an arbitrary object containing information about the "place" where this element was configured. Used by Guice in the production of descriptive error messages.

        Tools might specially handle types they know about; StackTraceElement is a good example. Tools should simply call toString() on the source object if the type is unfamiliar.

        Specified by:
        getSource in interface Element

      • getKey

        public Key<T> getKey()

      • getDependency

        public Dependency<T> getDependency()
        Since:
        4.0

      • acceptVisitor

        public <T> T acceptVisitor​(ElementVisitor<T> visitor)
        Description copied from interface: Element
        Accepts an element visitor. Invokes the visitor method specific to this element's type.
        Specified by:
        acceptVisitor in interface Element
        Parameters:
        visitor - to call back on

      • initializeDelegate

        public void initializeDelegate​(Provider<T> delegate)
        Sets the actual provider.
        Throws:
        IllegalStateException - if the delegate is already set

      • applyTo

        public void applyTo​(Binder binder)
        Description copied from interface: Element
        Writes this module element to the given binder (optional operation).
        Specified by:
        applyTo in interface Element
        Parameters:
        binder - to apply configuration element to

      • getDelegate

        public Provider<T> getDelegate()
        Returns the delegate provider, or null if it has not yet been initialized. The delegate will be initialized when this element is processed, or otherwise used to create an injector.

      • getProvider

        public Provider<T> getProvider()
        Returns the looked up provider. The result is not valid until this lookup has been initialized, which usually happens when the injector is created. The provider will throw an IllegalStateException if you try to use it beforehand.

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class Object