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I know the basics of writing an entity bean. I’ve also used the reverse engineering ejb 3 feature to create the classes from the database table?
Why is there a table.java and tableId.java file? tableId.java file has all the fields. Its confusing. Is table.java the primary key class?
How do I code the persistence.xml file? Can you give me a sample or point me to a good resource?
When you don’t have a primary key setup for a table, or you have a composit key (consisting of 2 or more fields) then an object representing those fields is generated. In the case that you have no primary key set, one is generated for you that automatically uses *every field* of the table… this is because in order to use mapping technology like Hibernate, JPA or EJB3 entities you have to have a PK reference for every record in a table, otherwise there is no way for the persistence engine to differentiate the records from eachother.
