Frequently, deploying data access applications involves more than
installing your WAR or EAR file onto a server. Deployment can include tasks
for configuring your application to use the data access resources of the server
and overall run-time environment.
Before you begin
You can only deploy application code that is assembled into the appropriate
modules. The topic
Assembling data access applications
provides
guidelines for this process.
About this task
Perform the following steps if your application requires access to
a relational database (RDB). If your application requires access to a different
type of enterprise information system (EIS), such as an object-oriented database
or the Customer Information Control System (CICS), consult the topics
Resource adapters
and
Accessing data using J2EE Connector Architecture connectors
.
Procedure
- If your RDB configuration does not already exist:
- Create a database to hold the data.
- Create tables required by your application.
- If your application uses CMP entity beans to access the data
- You can create the tables using the data definition language (DDL) generated
from the enterprise bean configuration. For more information, see Recreating
database tables from the exported table data definition language.
- If your application uses BMP entity beans, or does not use entity
beans
- You must use your database server interfaces to create the tables.
You can also use the EJB to RDB Mapping wizard of an assembly
tool to create your database tables for either type of entity bean. Select
the top-down mapping option in the wizard. Keep in mind, however, that this
option does not give you direct control in naming the RDB elements or choosing
column types. Additionally, because the top-down process is automatic, it
might not provide mappings to reflect the precise relationships that you intend.
If
you use the Application Server Toolkit (AST), consult the that product information
center about the mapping wizard. To learn about all of your assembly tool
options, consult the Assembly tools
article
in this information center.
- Check Data source minimum required settings, by vendor
to see any database
vendor requirements for connecting to an application server.
- If necessary, map your entity beans to the database tables through
the meet-in-the-middle mapping option of an assembly tool. This
step is necessary only if you did not create your database schema through
the top-down mapping option, did not generate your mapping relationships through
bottom-up mapping, or did not generate mappings during the application assembly
process. For information on the top-down mapping option refer to the Application
Server Toolkit information center.
- Install your application onto the application server. Consult Installing J2EE application files
. When you install
the application, you can alter data access settings that were made during
application assembly, or set them for the first time if they were omitted
from the assembly process. These settings include resource bindings and resource
authentication aliases, which are addressed in the following substeps:
- Bind application resource references to the data sources, or
other resource objects, that provide database connectivity. For
details on the concept of binding, see the Data source lookups for enterprise beans and Web modules
topic.
Tip: After deployment, you can use the WebSphere Application Server
administrative console to alter resource bindings. Click Applications > Enterprise
Applications > application_name, and select the link to the appropriate
mapping page. For example, if you want to alter the binding of an EJB module
resource, you might click 1.x CMP bean data sources or 2.x CMP bean
data sources. For a Web module resource, click Resource references.
- Define authentication alias data for resources that must be
authenticated with the backend through container-managed authorization.
In this security configuration, WebSphere Application Server performs
EIS signon for data source or connection factory connections. Consult the J2EE connector security
topic for detailed
reference on resource authentication.
- Start the deployed application files using the administrative console , the wsadmin startApplication command, or your own Java program.
- Save the changes to your administrative configuration.
- Test the application. For example, point a Web browser at the URL
for a deployed application and examine the performance of the application.
Results
When you deploy an application that uses a
DB2 UDB for i5/OS back-end database, you might find the following exception
in the SystemOut.log file:
PMGR6022E: Error using adapter to create or execute an Interaction
This
type of error indicates that you deployed an application with Container-managed
persistence (CMP) enterprise beans that were originally configured to access
a DB2 database on Windows, Linux, or a supported UNIX system. Using the administrative
console, uninstall the affected CMP applications, then reinstall the applications
with the new database setting. Remember to select
Deploy enterprise beans;
on the EJB deploy panel, select the appropriate version of your DB2 UDB for
i5/OS database.
What to do next
If the application does not perform as desired, update the application, then save and test it again.