[rules-users] Updates with property change on facts. How???

[Jason Smith]

I implemented the following listener for my bean and I am calling .update() directly on the StatefulKnowledgeSession.

QUESTION 1:  Is there a better way?  The old API supported .insert(fact,boolean).  The new one does not.  I am not finding any documentation that explains the new API (version 5.0.1).

QUESTION 2: Why is this calling my rule twice?  The rule is getting called twice, and the second time it's called, the entry conditions are invalid!  That is, I changed the bean in a way that invalidates the WHEN condition.  The rule still gets called twice.  

How do I even begin to go about troubleshooting this?  This same behavior was happening with Drools 4 and the old API as well.



    private class InnerPropertyChangeListener implements PropertyChangeListener
    {
     private final InternalFactHandle factHandle;
     private final Object fact;
     private final StatefulKnowledgeSession session;
     
     public InnerPropertyChangeListener(InternalFactHandle factHandle, Object fact, StatefulKnowledgeSession session)
     {
      this.factHandle = factHandle;
      this.fact = fact;
      this.session = session;
     }
     
  @Override
  public void propertyChange(PropertyChangeEvent evt) 
  {
   System.out.println("****** UPDATING " + evt.getPropertyName() + ": " + 
     "\n        NEW:    " + StringUtil.indent(BeanUtil.printObject(evt.getNewValue()),16) +
     "\n        OLD:    " + StringUtil.indent(BeanUtil.printObject(evt.getOldValue()),16));
   if((evt.getNewValue() == null && evt.getOldValue() != null) || !evt.getNewValue().equals(evt.getOldValue()))
   {
    session.update(factHandle, fact);
   }
  }
    }





Jason Smith