Modify document property during documentModified Event

Hi,

Any ideas on what I'm not doing? Basically I'm trying to update a property
of a document as it is being saved from an edit via the front-end UI. I'm
trying to do this via an EventListener, but any changes I make are not
persisted. My listener is something like:

public class MyEventListener extends AbstractEventListener implements
AsynchronousEventListener {
  public void handleEvent(CoreEvent coreEvent) throws Exception {
    String eventId = coreEvent.getEventId();
    if (eventId.equals("documentModified")) {
      doc.setProperty("myschema", "myproperty", "SOME_VALUE");
    }
  }
}

Any ideas? In my actual implementatation the value is computed from other
just entered fields - is there a better way to implement 'computed' fields?

Thanks,

Sean

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Dr. Sean Radford, MBBS, MSc
w: http://www.tacola.com
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