HI,
I have requirement where I have to map a single Alarm object to two tables as ActiveAlarm and HistoricalAlarms. The columns in both the table are the same. I hope it is not an association.

Can someone help me out in solving this using hibernate.

Hi,

Its wise to have one class per table.

Since you have two tables with the same column. Possibly keep a base class as Alarm. Then create two others class for the table and extend the class Alarm.

Any comments???????????

Are trigger an option ? If so it shouldn't be hard to do your requirement.

Thanks Ramnathan for your support.
I have tried the same as you suggested by I have a requirement where my activealarm has to be converted into historicalalarm and then the historicalalarm has to be inserted into the historicalalarm table using spring HibernateTemplate. When I do

public void addAlarms(Alarm alarm) {
HistoricalAlarm halarm = (HistoricalAlarm)alarm;
getHibernateTemplate().save(halarm);

}
I get a classcastexception.
Exception in thread "main" java.lang.ClassCastException: com.eci.alarm.dao.ActiveAlarm
at com.eci.alarm.dao.AlarmDaoImpl.addAlarms(AlarmDaoImpl.java:20)
at com.eci.alarm.dao.Main.main(Main.java:18)

Here the Alarm object is a superclass & activealarm and historicalalarm are the subclasses.

Only way to do this happen is that I have to manually write code to map ActiveAlarm object to HistoricalAlarm object and then save the object to database. Is there any other way to do this with manual mapping of objects.

Santhamohan

Hi,

I suppose the object you pass into the method is an activeAlarm. So you need to clone the object to HistoricalAlarm and viceversa.

If you get different objects of Alarm in the runtime. Do an instanceof check to prevent from ClassCastException
i.e)
public void addAlarms(Alarm alarm) {
if(alarm instanceof HistoricalAlarm){
HistoricalAlarm halarm = (HistoricalAlarm)alarm;
getHibernateTemplate().save(halarm);
}else{
// place your activealarm here
}
}

All the Best

Ramnath is correct.

U can map the active alarm object to the user data and clone the same on the server. Typecast the same to Historical alarm and then save it separately.Use deepClone() which might save u lots of coding.

Any comments???