You can also create assertion conditions in a standalone assert activity in a BPEL process service component. The assertion specifies an XPath expression that, when evaluated to false, causes a BPEL fault to be thrown from the activity.

The bpelx:assert extension implements assertions in the standalone assert activity:

<bpelx:assert name="Assert1" expression="string" message="string"/>

For information about using the standalone assert activity, see How to Create Assertion Conditions.