Entitymanager Persistent

[poyge394]

Hi,

i have 2 entity bean, Rollingstock and Schedule.
Hear is some code:

rollingstock = new Rollingstock();
rollingstock.setNextRoute( "STH" );
rollingstock.setRoute( "HALL" );
schedule = new Schedule();
rollingstock.setSchedule( schedule );

So now i whant to persist the entitys, i thought that i just neded to do:

manager.persist(rollingstock);

then bouth rollingstock and schedule would be persist, but i get a exception when i do that.
i must do this to get both persist:

manager.persist(rollingstock);
manager.persist(schedule);

is thair any better way to persist entitys, Because in my Rollingstock entity i have a lot off relations, so when i get a Rollingstock i just whant to run persist(rollingstocko);
now i must take out evrything and do persist on each entity.

any clarification ?

[fhh]

What is the exception?

Regards

Felix

[alrubinger]

Well, unless the relationship defined is annotated with @Cascade (CascadeType.PERSIST), you can't persist one entity and expect the relationship to be inserted as well.

So that's one solution.

However, I typically keep the Cascading strategies to NONE as a default (to keep close tabs on what operations the container might do without my explictly telling it so; this is a perference only), and would do the following:

// Create Rollingstock
rollingstock = new Rollingstock();
rollingstock.setNextRoute( "STH" );
rollingstock.setRoute( "HALL" );

// Create Schedule
schedule = new Schedule();

// Persist Each
manager.persist(rollingstock);
manager.persist(scheulde);

// Associate (bi-directionally) after Persisted
rollingstock.setSchedule(schedule);
schedule.setRollingstock(rollingstock);