A resource reference supports application access to a resource (such as a data source,
URL, or mail provider) using a logical name rather than the actual name in the runtime environment.
This capability eliminates the necessity to alter application code when you change the resource
runtime configurations.
Before you begin
This topic guides you through updating the resource references of an enterprise application
that you assembled previously. The topic, Assembling applications, details the assembly
procedure.
About this task
Resource references are declared in the deployment descriptor by the application provider.
At some point in the application deployment process, you must bind the resource reference to the
actual name of the resource in the run time environment. When you create a connection factory or
data source in the application server, the application server provides a JNDI name that a component
can use to access that connection factory or data source. The application server uses an indirect
name with the java:comp/env prefix. For example:
- When you create a data source, the default JNDI name is set to
jdbc/data_source_name.
- When you create a connection factory, its default name is
eis/j2c_connection_factory_name.
If you override these values by specifying your own, retain the java:comp/env prefix. An
indirect JNDI name allows the connection management infrastructure to access to any data from the
resource reference that is associated with the application. This allows you to better manage
resources based on the settings for authentication, isolation level, sharing scope, and resolution
control.This topic describes how to update the resource references of an enterprise application
using an assembly tool. After you define the resource reference, you can perform an indirect JNDI
lookup using the java:comp/env context.
Procedure
-
Start an assembly tool.
-
If you have not done so already, configure the assembly tool for work on Java Platform,
Enterprise Edition (Java EE) modules.
-
Import the enterprise application (EAR file) that you want to change into the EJB
project.
-
Display the resource references for the type of module:
- If an enterprise bean uses the resource reference:
- Expand the name of the EAR file.
- Expand EJB Modules.
- Expand the EJB module wanted.
- Expand the section for the appropriate type of enterprise bean (Session Beans or
Entity Beans).
- Expand the enterprise bean.
- If a servlet uses the resource reference:
- Expand the name of the EAR file.
- Expand Web Modules.
- Expand the web module wanted.
- If an application client uses the resource reference:
- Expand the name of the EAR file.
- Expand Application Clients.
- Expand the application client module wanted.
-
Right-click the module whose resource references you want to change and click Open With >
Deployment Descriptor Editor.
-
For servlets and application clients, click Add. For EJB modules, select the particular
bean and click Add.
-
Select the resource reference option and click Next.
-
Specify the settings for the resource reference, and click Finish.
- Optional:
Select the References tab and, under WebSphere Extensions, select an isolation
level.
If you choose to forego this step, the isolation level defaults to TRANSACTION_NONE.
- Optional:
Under WebSphere Bindings, specify a JNDI name.
If you choose to forego this step you can set (or override) the binding when the application
is deployed.
-
Close the deployment descriptor editor and save your changes.
Results
Files for the updated module are shown in the Project Explorer view.
What to do next
Verify the contents of the updated enterprise application in the Project Explorer view.
Then, deploy your enterprise application.You can generate EJB deployment code and deploy an EJB
module to a target server in one step. In the Project Explorer view, right-click on the EJB project
and click Deploy. See also the topic, Deploying EJB modules.