Ordered Collection events
first 
A first event indicates that the first element of the Ordered Collection part has changed. 
isEmpty 
An isEmpty event indicates that the ordered collection is empty. 
last 
A last event indicates that the last element of the Ordered Collection part has changed. 
self 
A self event indicates that the value of the target part itself has changed. 
size 
A size event indicates the number of elements in the Ordered Collection part has changed. 
Last modified date: 01/29/2015