The application can perform outbound communications using CCI interface,
and it can create MDB to handle inbound communications.
The following process describes what happens when an application uses CCI
to send and receive messages:
- The application requests a connection to the EIS through the JNDI name
of the connection factory for the SNA JCA LU62 Connector. The factory creates
the connection using the connection properties predefined in the J2C console
page of WebSphere® Application
Server. The application can also set the TP name predefined in the J2C console
page.
- When the application has an established connection, it performs an interaction
verb to send and receive messages. The interaction verb has the following
properties: verb type (send or receive), timeout, input record, and output
record.
- To perform the interaction, the SNA JCA LU62 Connector converts the input
record or input message into string and then invokes the corresponding API
of underlying EIS according to the interaction verb type.
- The SNA JCA LU62 Connector returns the output record or message to the
application.
- The application continues with the interaction verb or closes the connection.
The following process describes what happens when an application uses MDB
to handle inbound message asynchronously:
- User creates a MDB that implements the interface of the Resource Adapter's
message type. The activation specification values and JNDI name of activation
specification should also be specified while creating MDB.
- When the MDB is deployed to the Application Server, the Application Server
will look up the Resource Adapter by matching the message type and activationSpec JNDI
name of the Resource Adapter and the MDB.
- The activationSpec instance of MDB and a MessageEndpointFactory instance
will be transferred to the Resource Adapter for validation and registration.
After the MDB is activated, the MDB is ready to receive messages.
- The MDB can receive two types of messages: one type is pure inbound message
that originates from partner host, which is called unsolicited message; the
other type is the outbound reply message from partner host after the application
sends outbound message at first by using CCI, which is called solicited message.
- For the unsolicited inbound message that comes from EIS, the resource
adapter will create an endpoint by calling createEndPoint() method
of MessageEndpointFactory instance passed by Application Server when
MDB is activated. Then JCA LU62 Connector will call onIncomingMessage method
of the endpoint to notify the MDB of message arrival.
- For the solicited outbound reply message, the JCA Connector will match
the activation specification with the custom property of the connection factory.
Then JCA LU62 Connector will call onOutgoingReplyMessage method of
the endpoint to notify the MDB of message arrival.
- When the Application Server stops or the MDB is undeployed, the Application
Server will notify the resource adapter that the MDB is deactivated. Then
the adapter will not deliver message to the MDB.