IBM BPM, V8.0.1, All platforms > Get started with IBM BPM > Key concepts > Bindings > Binding types > Generic JMS bindings
Generic JMS bindings overview
Generic JMS bindings are non-JCA JMS bindings that provide connectivity between the Service Component Architecture environment and JMS systems that are compliant with JMS 1.1 and that implement the optional JMS Application Server Facility.
Generic JMS bindings
The major aspects of Generic JMS import and export bindings include the following:
- Listener port: enables non-JCA-based JMS providers to receive messages and dispatch them to a Message Driven Bean (MDB)
- Connections: encapsulate a virtual connection between a client and a provider application
- Destinations: used by a client to specify the target of messages it produces or the source of messages it consumes
- Authentication data: used to secure access to the binding
Generic JMS import bindings
Generic JMS import bindings allow components within your SCA module to communicate with services provided by external non-JCA 1.5-compliant JMS providers.
The connection part of a JMS import is a connection factory. A connection factory, the object a client uses to create a connection to a provider, encapsulates a set of connection configuration parameters defined by an administrator. Each connection factory is an instance of the ConnectionFactory, QueueConnectionFactory, or TopicConnectionFactory interface.
Interaction with external JMS systems includes the use of destinations for sending requests and receiving replies.
Two types of usage scenarios for the Generic JMS import binding are supported, depending on the type of operation being invoked:
- One-way: The Generic JMS import puts a message on the send destination configured in the import binding. Nothing is sent to the replyTo field of the JMS header.
- Two-way (request-response): The Generic JMS import puts a message on the send destination and then persists the reply it receives from the SCA component.
The receive destination is set in the replyTo header property of the outbound message. A message driven bean (MDB) is deployed to listen on the receive destination, and when a reply is received, the MDB passes the reply back to the component.
The import binding can be configured (using the Response correlation scheme field in Integration Designer) to expect the response message correlation ID to have been copied from the request message ID (the default) or from the request message correlation ID.
For both one-way and two-way usage scenarios, dynamic and static header properties can be specified. Static properties can be set from the Generic JMS import method binding. Some of these properties have special meanings to the SCA JMS runtime.
It is important to note that Generic JMS is an asynchronous binding. If a calling component invokes a Generic JMS import synchronously (for a two-way operation), the calling component is blocked until the response is returned by the JMS service.
Figure 1 illustrates how the import is linked to the external service.
Figure 1. Generic JMS import binding resources
Generic JMS export bindings
Generic JMS export bindings provide the means for SCA modules to provide services to external JMS applications.
The connection part of a JMS export is composed of a ConnectionFactory and a ListenerPort.
A Generic JMS export has send and receive destinations.
- The receive destination is where the incoming message for the target component should be placed.
- The send destination is where the reply will be sent, unless the incoming message has overridden this using the replyTo header property.
An MDB is deployed to listen to requests incoming to the receive destination specified in the export binding.
- The destination specified in the send field is used to send the reply to the inbound request if the invoked component provides a reply.
- The destination specified in the replyTo field of the incoming message overrides the destination specified in the send field.
- For request/response scenarios, the import binding can be configured (using the Response correlation scheme field in Integration Designer) to expect the response to copy the request message ID to the correlation ID field of the response message (default), or the response can copy the request correlation ID to the correlation ID field of the response message.
Figure 2 illustrates how the external requester is linked to the export.
Figure 2. Generic JMS export binding resources
