Resource (Java EE 5 SDK)

javax.annotation Annotation Type Resource

@Target(value={TYPE,FIELD,METHOD})
@Retention(value=RUNTIME)
public @interface Resource

The Resource annotation marks a resource that is needed by the application. This annotation may be applied to an application component class, or to fields or methods of the component class. When the annotation is applied to a field or method, the container will inject an instance of the requested resource into the application component when the component is initialized. If the annotation is applied to the component class, the annotation declares a resource that the application will look up at runtime.

Even though this annotation is not marked Inherited, deployment tools are required to examine all superclasses of any component class to discover all uses of this annotation in all superclasses. All such annotation instances specify resources that are needed by the application component. Note that this annotation may appear on private fields and methods of superclasses; the container is required to perform injection in these cases as well.

name

public abstract String name

The JNDI name of the resource. For field annotations, the default is the field name. For method annotations, the default is the JavaBeans property name corresponding to the method. For class annotations, there is no default and this must be specified.

默认值:

""

type

public abstract Class type

The Java type of the resource. For field annotations, the default is the type of the field. For method annotations, the default is the type of the JavaBeans property. For class annotations, there is no default and this must be specified.

默认值:

java.lang.Object.class

authentication

public abstract Resource.AuthenticationType authentication

The authentication type to use for this resource. This may be specified for resources representing a connection factory of any supported type, and must not be specified for resources of other types.

默认值:

CONTAINER

shareable

public abstract boolean shareable

Indicates whether this resource can be shared between this component and other components. This may be specified for resources representing a connection factory of any supported type, and must not be specified for resources of other types.

默认值:

true

mappedName

public abstract String mappedName

A product specific name that this resource should be mapped to. The name of this resource, as defined by the name element or defaulted, is a name that is local to the application component using the resource. (It's a name in the JNDI java:comp/env namespace.) Many application servers provide a way to map these local names to names of resources known to the application server. This mapped name is often a global JNDI name, but may be a name of any form.

Application servers are not required to support any particular form or type of mapped name, nor the ability to use mapped names. The mapped name is product-dependent and often installation-dependent. No use of a mapped name is portable.

默认值:

""

description

public abstract String description

Description of this resource. The description is expected to be in the default language of the system on which the application is deployed. The description can be presented to the Deployer to help in choosing the correct resource.

默认值:

""

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