I'll dive right into a simple example to explain my question:



log_entry.level references log_level.id
a unique constraint on log_level.name


("ERROR" etc. acts here as a natural id, such that the row of log_level is identified in a unique way)

Now for the Hibernate Mapping for the log_entry:

I could just introduce a property for the level, which would yield something like a setLevel(int) method, by simply setting the foreign key.
Or I could use a many-to-one mapping, that would result in a setLevel(LogLevel) method, but this way I would have to use a LogLevel object.

But is it possible to create a mapping for the log_entry, such that you cat set the log level of a log entry by using e.g. setLevel("ERROR")?

I've looked into several mapping chapters but have not found anything with which I could realize the mapping above. Is it possible to realize with Hibernat at all?

Hello,
pick option 2 (manyToOne), you can do something like this:



make sure to use field access instead of property.

Does this really solve the problem? The setLogLevel("ERROR") will create a new LogLevel, but when persisting, hibernate doesn't know the primary key (in the example above: 1). The missing step here is to look for the primary key 1 with the (unique) name "ERROR" before persisting.

Hello,
The only other option i can suggest is using the actual LogLevel object, with any access type you prefer, and the logic can be on the DAO layer. Here is a sample:



you hit the database twice in this case.