Release 10.1A: OpenEdge Development:
Messaging and ESB

Managing connections and sessions

In order to use the messaging capabilities of JMS and Sonic MQ, a connection must be created to the SonicMQ Broker. An active connection receives messages. A session is a single-threaded context for sending and receiving messages. Since the 4GL is single-threaded, there is no compelling reason for multiple sessions per connection, nor for exposing the distinction between sessions and connections. In the context of the 4GL-JMS API, the term session refers to the combination of a session and a connection.

Note: In JMS, a Java client can create several sessions per connection.

When more than one session per connection is required (for example, to send and receive messages concurrently), a second session is used implicitly in the OpenEdge Adapter for SonicMQ, transparent to the 4GL programmer.

The following sections describe:

Creating a JMS session
Deleting a JMS session
Connection options
Managing fail-over support
Setting and getting JMS connection and session attributes
Connecting to the OpenEdge Adapter for SonicMQ
Load balancing
Client persistence
Fault tolerance
Establishing session control
Accessing message delivery parameters
Request/Reply
Message selectors