Event

The Event tab has the following fields.

Field

Description

Candidate Event Key

Expression built from the data of the incoming file change event. This expression should evaluate to a string and it is compared to the "key" field of the activity’s input. If the Candidate Event Key and the activity’s key match, then the process accepts the incoming message.

For example, you may have sent an HTTP request earlier in the process, and you may be waiting for a response from the HTTP server. You may specify a requestID as an attribute of the HTTP request and responseTo attribute on the Wait for HTTP request activity. The HTTP server presumably set the responseTo attribute of its response to the same value as the requestID attribute of the request. You would then specify the responseTo attribute as the Candidate Event Key and the requestID attribute of the HTTP request as the "key" in the Input tab.

This expression is specified in XPath, and only data from the incoming event is available for use in this XPath expression. For more information about XPath expressions, see TIBCO ActiveMatrix BusinessWorks™ Process Design.

Event Timeout (msec)

A message may arrive before this activity is executed. This field specifies the amount of time (in milliseconds) a message waits if it is received before this activity is executed. If the event timeout expires, an error is logged and the event is discarded.

If no value is specified in this field, the message waits indefinitely. If zero is specified, the event is discarded immediately, unless this activity has already been reached.

Note: When building an expression in the Candidate Event Key field, only data from the incoming event is available. This is because you want to place an expression containing incoming event data in the Candidate Event Key field. When the results of this expression match the results of the expression in the "key" item on the Input tab, the Wait For HTTP Request activity proceeds.