EventListener

The EventListener activity is a process starter that creates a process instance for incoming events in a specified space. It can listen for the Put, Take, Expire, Seed, and Unseed events, which occur in the specified space.

General

In the General tab, you can specify the activity name and a space connection.

The following table describes the fields in the General tab of the EventListener activity:

Field Module Property? Description
Name No Specifies the name to be displayed as the label for the activity in the process.
Space Connection Yes Click the icon to select a space connection that defines how the application joins the space.

The events that occur in the space are monitored with the defined distribution role of the selected space connection.

If no matching space connections are found, click Create Shared Resource to create one. See Creating a Metaspace Connection for details.

Description

In the Description tab, you can enter a short description for the EventListener activity.

Advanced

In the Advanced tab, you can specify the operations that you want to listen for.

The following table describes the fields in the Advanced tab of the EventListener activity:

Field Module Property? Description
Filter Yes Specifies a filter string.

A filtered event listener only returns entries that match the specified filter.

The way filters work in the plug-in is similar to the way message selectors work in JMS.
Note: Ensure that the filter syntax is correct according to the TIBCO ActiveSpaces documentation. If an invalid filter is given, no results are reported.

See TIBCO ActiveSpaces User’s Guide for detailed information on how to use filters.

Time Scope Yes Select a time scope to narrow down the period of time of interest:
  • ALL: the listener starts with all the entries currently in the space at creation time (which are presented as an initial set of Put events). The set is continuously updated according to changes in the space. By default, this option is selected.
  • NEW: the listener starts empty and is updated only with events related to new or overridden entries in the space.
  • NEW_EVENTS: the listener starts empty, and is updated with all events that occur in the space after creation time. Unlike the NEW time scope, NEW_EVENTS includes events (such as Take and Expire events) related to entries already contained in the space at creation time.
Distribution Scope No Select a distribution scope to narrow down the set of entries being browsed:
  • ALL: listens for events related to all entries in the space. By default, this option is selected.
  • SEEDED: listens only for events associated with the entries in the space that are seeded by this member. It is empty unless the member is a seeder in the space.
Listen for Put Events Yes Select this check box to enable TIBCO ActiveSpaces to notify applications whenever a tuple is inserted, updated, or overwritten in the space. By default, this check box is selected.
Listen for Take Events Yes Select this check box to enable TIBCO ActiveSpaces to notify applications whenever a tuple is removed from the space. By default, this check box is selected.
Listen for Expire Events Yes Select this check box to enable TIBCO ActiveSpaces to notify applications whenever a tuple has expired in the space. By default, this check box is selected.
Listen for Seed Events Yes Select this check box to enable TIBCO ActiveSpaces to notify applications whenever a redistribution occurs after an existing seeder leaves the space and the local node is now seeding additional entries.
Note: This field is displayed only when you select SEEDED from the Distribution Scope list.
Listen for Unseed Events Yes Select the check box to enable TIBCO ActiveSpaces to notify applications whenever a redistribution occurs after a new seeder joins the space and the local node stops seeding some of the entries.
Note: This field is displayed only when you select SEEDED from the Distribution Scope list.
Sequence Key No Specifies which processes run in order. Processes with the same sequence key are executed sequentially in the order in which the processes were created.
Custom Job Id No Specifies a custom job ID for the process instance. This ID is displayed in the TIBCO Administrator View Service dialog, and it is also available in the $_processContext process variable.

Conversations

A conversation can develop between a process and its clients, a process and its back-end services, and so on. A conversation is always initiated by one activity and joined by other activities.

You can use the following icons to manage conversations:

  • Click the Joining Existing Conversations icon to join multiple conversations.
  • Click the Add New Conversation icon to initiate a conversation.

For more details about conversations, see TIBCO ActiveMatrix BusinessWorks Application Development.

Output

In the Output tab, you can find the operation results.

The following table describes the fields in the Output tab of the EventListener activity:

Output Item Data Type Description
Type String Indicates the event type that the Event Listener activity listens for.

The value can be PUT, TAKE, EXPIRE, SEED, or UNSEED.

Tuple String Indicates the matched tuples in the associated space.