Need help with Hibernate? Read this first:
http://www.hibernate.org/ForumMailingli ... AskForHelp


Hi @all

dont know if it is possible but i try the following:

-----------------------------------------------------------------------
db-schema:

table: week
attributes: id, namekey

table: day
attributes, id, namekey

n:m relation between week and day => n:m table: week_days

table: week_days
with attributes: id (week), id (day), dinner (string)

-----------------------------------------------------------------------

now i try the annotated class Dinner
@Entity
@Table (name="dinners", schema="hotelmenu")
public class Dinner {

private Week week;
private Map<Day, String> htlDinners;

@ManyToOne
@JoinColumn(name = "week_id")
public Week getWeek() {
return this.week;
}
+setter for week

@ManyToOne
@JoinColumn (name= "day_id")
@MapKey (name= "day_id")
@Column (name = "wd_dinner") //for String in Map
public Map<Day, String> getHtlDinners () {
return htlDinners;
}
+setter for htlDinners

+equals & hash
}

is it possible to map a java.util.Map like this or am i missing something?
btw. what is the @MapKey stand for?

cheers manakin

Hi Manakin,


You can map entities relations as a map. The MapKey annotation should hold
the

1. Property of a mapped entity to be used as a key (the standard MapKey)
2. Or, a joined column (Hibernate's MapKey)

You can read about Hibernate and maps here (on my blog): http://jroller.com/page/eyallupu?entry=hibernate_true_maps_support
and here: http://jroller.com/page/eyallupu?entry=using_annotations_to_persist_java

Eyal Lupu