Replace the word
this.Location
with
this.LocationParameter1
to get
location = new Location( this.LocationParameter1 ),
on line 232 of Appointment_SendNotification.java.
Reason: if you have an entity Location in your model and a parameter Location in a java-action the parameter Location is internally Replaced with LocationParameter1 to prevent naming conflicts. This may happen will all javaactions.
In general the parameters should be written in lowercase and an entity should start with a capital.