Configuring IMS connection factories

You use the IMS™ connection factory in your application to interact with the IMS TM resource adapter. Through the IMS connection factories, you create pre-configured connections to the IMS Transaction Manager (IMS TM).

Connections between the IMS TM resource adapter and IMS Connect can be managed or non-managed.

Managed connections are connections that are managed by a Connection Manager in a Java™ EE application server such as WebSphere® Application Server. In a managed environment, applications do not need to create EIS connections. Instead, they request connections from the Java EE Connection Manager. Non-managed connections, however, are obtained directly by applications from the IMS TM resource adapter.

The type of physical connection between the IMS TM resource adapter and IMS Connect can be one of the following connection types:

TCP/IP socket
Local Option connection that uses cross-memory z/OS® program calls

With either types of connections, your application uses a Java EE Connection Architecture (JCA) connection factory to obtain a connection to IMS Connect.

When your application uses managed connections, all connections between the IMS TM resource adapter and IMS Connect are persistent. A connection is not opened and closed for each interaction. Instead, it can remain open and can be serially reused by multiple interactions, which provides better utilization of CPU and memory resources. Your Java EE application server administrator configures the connection factory at deployment time.

A non-managed connection must be opened and closed by the application that uses it. Your application must create and configure the connection factories that it needs at run time.

Recommendation: Use managed connections, and get a reference to the appropriate connection factory by using JNDI lookup.

The IMS TM resource adapter supports only persistent connections to IMS Connect. In a managed environment, persistent connections are serially reused by application components, without the need to disconnect and reconnect between each use. When using TCP/IP socket connections, application components can use either dedicated or shareable persistent socket connections between the IMS TM resource adapter and IMS Connect. Shareable persistent socket connections use client IDs that are generated by the IMS TM resource adapter and are not visible to the application that uses the shareable socket.

Recommendation: Always use shareable TCP/IP sockets unless there is some overriding requirement to use dedicated socket connections or Local Option connections. Dedicated persistent socket connections use client IDs that are specified by the application. When using Local Option connections, only shareable persistent connections are supported.