Release 10.1A: OpenEdge Development:
Messaging and ESB

> ## Accessing message delivery parameters

> Message delivery parameters set on the Session object are used as defaults for all messages sent in that session. The default can be changed by setting the parameters of the publish procedure call, the sendToQueue procedure call, or the requestReply procedure call. These values cannot be changed after the beginSession procedure is called.

> Table 4–8 lists the methods for setting and getting delivery parameters.

> Table 4–8: Setting and getting delivery parameters
> Setting | Getting
> --- | ---
> setDefaultPriority procedure setDefaultTimeToLive procedure setDefaultPersistency procedure | getDefaultPriority function getDefaultTimeToLive function getDefaultPersistency function

> ##### Setting the maximum number of messages

> The default maximum number of active JMS messages in a 4GL session is 50. This is the maximum number of messages that have been created, but not deleted by the application. To change the default, the main procedure of the 4GL application must include the JMS-MAXIMUM-MESSAGES global variable definition.

> Note: If you exceed the limit on the JMS-MAXIMUM-MESSAGES global variable, an error is returned.

> ##### Discardable messages

> SonicMQ supports a `DISCARDABLE` message delivery mode for messages published to a topic. When a message with the delivery mode `DISCARDABLE` is published to a topic and the topic’s queue is full, the message is automatically deleted. An application controls message delivery mode using the publish procedure and the setDefaultPersistency procedure.

Copyright © 2005 Progress Software Corporation www.progress.com Voice: (781) 280-4000 Fax: (781) 280-4095