Versions of WebSphere Application Server previous to Version 5.0 provided
an initial implementation of the J2EE Connector Architecture (JCA) specification,
Version 1.0. This implementation provided basic run time support based on
the final JCA 1.0 Specification, but it was not a complete implementation.
Version 5.0 of the product provides a complete implementation of the JCA
1.0 Specification, which supports:
- Connection sharing (res-sharing-scope).
- Get/use/close programming model for connection handles.
- Get/use/cache programming model for connection handles.
- XA, Local, and No Transaction models of resource
adapters, including XA recovery.
- Security options A and C per the specification.
- Applications with embedded .rar files
As of Version 6.0, the product provides a complete implementation of the
JCA 1.5 Specification, which supports:
- All the features of the JCA 1.0 Specification.
- Deferred enlistment transaction optimization.
- Lazy connection association optimization.
- Inbound communication from an enterprise information system (EIS) to a
resource adapter.
- Inbound transactions from an EIS to a resource adapter.
- Work management, which enables a resource adapter to put work on separate
threads and to pass execution context (such as inbound transactions) to the
thread .
- Life cycle management, which enables a resource adapter to be stopped
and started.
If you move from one of the earlier implementations of the J2EE Connector
Architecture to the current implementation, be aware of the following:
- This version of the product supports the res-sharing-scope tag
within the resource reference (resource-ref) element. This tag was not available
in previous versions and defaulted to shareable connections. Beginning
with Version 5.0, WebSphere Application Server supports both shareable
and unshareable connections.
- The current product supports the Web container. Both enterprise bean
and Web components can utilize the J2EE Connector Architecture.
- Both connection handle usage patterns (get/use/close and get/use/cache)
are supported. The get/use/close pattern indicates that a connection is retrieved,
used, and closed all within the same transaction or method boundary. The
get/use/cache pattern indicates that you can cache a connection across transaction
or method boundaries.
- The current version supports additional authentication mechanisms. The
capability to support Options A and C per the JCA specification is provided,
as well as support for res-auth settings of either Application or Container.
In versions before Version 5.0, the res-auth setting was basically
ignored, therefore it was treated as if res-auth was set to Application.
If your existing applications have res-auth set to Container,
they might behave differently if you install them into a current environment
without any changes.
- As of Version 6.0, resource authentication for res-auth settings
of Container is preferably specified on the resource-reference mapping
during application deployment. Specification of container-managed authentication
on a data source or connection factory is deprecated.
- As of Version 5.0, you can no longer specify pool and subpool names. The
pool name is based on the data source or connection factory Java Naming and
Directory Interface (JNDI) name. Subpools were eliminated to provide better
performance.
- As of Version 6.0, configuration data formerly in the j2c.properties file
is now supported through the wsadmin scripting tool and the administration
console. A migration utility updates the resources.xml file (or files)
based on the settings in a j2c.properties file. A template j2c.properties file
is no longer placed in the installed directory tree, but run-time code remains
in place to process the file and favor its settings over those from the real
configuration.
For applications that use Web services and JCA connectors, be aware that
those generated on WebSphere Studio Application Developer -- Integration Edition
Version 4.1.1 can run unchanged on WebSphere Application Server Version 6.0
only if they are regenerated using WebSphere Studio Application Developer
-- Integration Edition Version 5.0 tools, or Rational Application Developer
tools. This limitation is because of the wsd14j.jar file. As delivered
in WebSphere Application Server Enterprise Version 4.1, the file is not fully
compliant with JSR 110 (because JSR 110 was not final at the time that Version
4.1 shipped). The wsd14j.jar file shipped with WebSphere Application
Server Version 6.0, of course, is compliant. However, because most of the
classes have the same package names and interfaces, BUT NOT ALL, the two wsd14j.jar files
cannot co-exist in the same WebSphere Application Server installation.
JDBC provider templates: important general migration tip
Always handle the jdbc-resource-provider-templates.xml file as read-only
. When updating this file, special consideration should be taken. Before installing
a PTF, you should save your updated jdbc-resource-provider-templates.xml file.
After applying the PTF, you will need to verify that the new jdbc-resource-provider-templates.xml file
has your correct entries. If the entries are not valid, you will have to
merge your changes into this new jdbc-resource-provider-templates.xml file
manually.