- The User home interface contains two finder methods
- findByPrimaryKey()
- findAllUsers()
- Each home interface must have a findByPrimaryKey() method
- Q: What is a primary key?
- A: A primary key is a serializable Java object whose value uniquely identifies an entity bean in the context of a given "system"
- The system designer determines an appropriate primary key for each entity bean type
- For the User EJB, the primary key is basically the login ID
- findByPrimaryKey() attempts to locate a User EJB based on the given primary key
- findAllUsers() returns a java.util.Enumeration that contains references to all of the users in the system
- Returning a java.util.Collection is also valid from V1.1 onward
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