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.