Info: How is Dao doing the update?

[Vijay Venkatachalam]

Hi,

Today I came one step close to understand the way GenericDao has implemented
the update in DB.  I thought this understanding might be of use to someone who 
is new
to CloudStack like myself. Please read on

Observation:
                Changes  in a setter in VO would never reflect in the DB.
public setName(String name) {
# it gets stored with the contents of argument "name" not "this.name"
                this.name  = "Name: " + name;
}
Reason:
                The setter functions of a VO are intercepted and 
UpdateBuilder.java stores the
argument in a private list "_changes" and this is what is used to update the DB
at a later stage and *not* the object present in the member variable 
"this.name".

Suggestion/Fix:
                In my case I had a function like the following
                private String counterParameters;
setCounterParameters(Map map) {
                //loop through all the entry sets
                // concatenate them as a tempString  store it like the following
this.counterParameters = tempString;
}

I changed it as

# Plain vanilla function that is intercepted for update
setCounterParameters(String counterParmaaters) {
                this.counterParameters = counterParameters;
}
#custom setter which changes values
setCounterParametersForUpdate(Map map)
{
                // loop through all the entry sets
                // concatenate them as a tempString
setCounterParameters(tempString);
}

Any other Recommendation?:
                Is there a better way to get the Fix done?


Thanks,
Vijay V.