Interface ObjectProvider

All Known Implementing Classes:
ApplicationMessageCatalogObjectProvider, AssetObjectProvider, AutobuildObjectProvider, EntityManagerObjectProvider, ServiceAnnotationObjectProvider, StaticObjectProvider, SymbolObjectProvider, ValueObjectProvider

public interface ObjectProvider

Object providers represent an alternate way to locate an object provided somewhere in the Registry. Instead of using a just the service id to gain access to a service within the Registry, object providers in different flavors are capable of vending, or even creating, objects of disparate types from disparate sources.

Object providers are consulted in a strict order, and the first non-null result is taken.

In many cases, an object provider searches for additional annotations on the element (usually a parameter, or perhaps a field) for which a value is required.

Method Summary
<T> T
provide(Class<T> objectType, AnnotationProvider annotationProvider, ObjectLocator locator)
          Provides an object based on an expression.

Method Detail


<T> T provide(Class<T> objectType,
              AnnotationProvider annotationProvider,
              ObjectLocator locator)
Provides an object based on an expression. The process of providing objects occurs within a particular context, which will typically be a service builder method, service contributor method, or service decorator method. The locator parameter provides access to the services visible to that context.

Type Parameters:
T -
objectType - the expected object type
annotationProvider - provides access to annotations (typically, the field or parameter to which an injection-related annotation is attached); annotations on the field or parameter may also be used when resolving the desired object
locator - locator for the context in which the provider is being used
the requested object, or null if this object provider can not supply an object
RuntimeException - if the expression can not be evaluated, or the type of object identified is not assignable to the type specified by the objectType parameter

Copyright © 2003-2012 The Apache Software Foundation.