Configure topics

A JMS topic is based on the publish/subscribe (pub/sub) messaging model, which enables an application to send a message to multiple applications. Pub/sub messaging applications send and receive messages by subscribing to a topic. A topic publisher (producer) sends messages to a specific topic. A topic subscriber (consumer) retrieves messages from a specific topic.

You configure topics explicitly or by configuring a JMS template that can be used to define multiple topics with similar option settings, as described in Configure JMS templates.

Note: To help manage recovered or rolled back messages, you can also configure a target error destination for messages that have reached their redelivery limit. The error destination must be targeted to same JMS server as the other topics in the module. See Programming WebLogic JMS.

Some topic options are dynamically configurable. When options are modified at runtime, only incoming messages are affected; stored messages are not affected.

To configure a topic:

If necessary, configure a JMS system module for the topic. See Configure JMS system modules.
Before creating a topic resource in a module, you can optionally create other quota, template, and destination key resources in the module that can be referenced from within the topic:
- Quotas are used to control the allotment of system resources available to topics. See Configure quotas for destinations.
- JMS Templates provide an efficient means of defining multiple topics with similar configuration settings. See Configure JMS templates.
- Destination keys allow you to define the sort order of messages that arrive on a specific topic. See Configure destination keys.
Create topics
After creating a basic topic, you can define a number of optional properties:
1. Configure general topic properties
  Configuring optional General topic properties includes selecting a destination key for sorting messages as they arrive on the topic, or selecting a JMS template if you are using one to configure properties for multiple topics.
2. Configure advanced topic parameters
  Configuring optional Advanced topic properties includes specifying unit-of-order parameters and attaching the credentials of message senders.
3. Configure topic thresholds and quota
  Define upper and lower byte and/or message thresholds for the topic, select a pre-configured quota specifying the maximum number of bytes or messages that the topic is allowed to store, or specify a maximum size allowed for messages on the topic.
4. Configure topic message delivery overrides
  Define message delivery override values, such as message priority and time-to-deliver values, that can override those specified by a message producer.
5. Configure topic message logging
  Enable the logging of message life cycle information into a JMS message log file. The content of the message log always includes message ID and correlation ID, but you can also configure information like message type and user properties.
6. Configure topic message delivery failure options
  Define default message delivery failure values, such as defining a message redelivery limit, selecting a message expiration policy, and specifying an error destination for expired messages.
7. Configure topic multicast parameters
  Define multicast parameters that enable the delivery of messages to a select group of hosts that subsequently forward the messages to subscribers.
If you skipped the targeting step when you created a topic, or want to modify the current targeting parameters, you can do so at anytime. See Target topics.
Optionally, add or remove security roles and policies to a topic. See Create topic security roles and Configure topic security policies.
In the event that you need to troubleshoot a topic, you can temporarily pause all message production, insertion (in-flight messages), and consumption operations on the topic. Topics can be paused either on a WebLogic Server restart or at runtime.
- Pause topic message operations on server restart Pause topic message operations on server restart
- Pause topic message operations at runtime Pause topic message operations at runtime