@javax.annotation.Resource

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Internal

Overview

The @Resource annotation marks a resource that is needed by the application. This annotation may be applied to a 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.

@Resource(lookup = "java:global/remote-hornetq")
private InitialContext externalContext;


Defined by JSR 250 "Common Annotations for the Java Platform".

Elements

name

The JNDI name of the resource.

If the annotation is applied to a field, the default value of the "name" element is the field name qualified by the class name. For example, in the following case:

package com.example;
public class MyClass {

    @Resource
    private DataSource ds;
}

the default name is "com.example.MyClass/ds"

"name" works with external JNDI contexts. For example, if "java:global/remote-hornetq" is the name of an external JNDI context imported locally, and "/jms/queue/playground" is the JNDI name of a remote destination bound in "java:jboss/exported" JNDI context by the remote server, then the queue can be injected locally as follows:

@Remote(name="java:global/remote-hornetq/jms/queue/remote-inbound")
private Queue remoteQueue;

lookup

The JNDI name of a resource that the resource being defined will be bound to.