JDBC: Accessing Relational Data

Persistence allows an object to outlive the process that created it.

The state of the object may be stored to disk and an object with the same state re-created at some point in the future.

public class User {
  String commonName; // Common name e.g. 'Joe Bix'
  String uid;        // Unique login name e.g. 'bix'
  ...                // getters, setters and other stuff

}
//------------------------------------
// Thread lifespan (transient instance)
User u = new User("Joe Bix", "bix");

CREATE TABLE User(
  commonName CHAR(80)
 ,uid CHAR(10) PRIMARY KEY
);
-- Persistent record (see Durability in ACID)
INSERT INTO User VALUES('Joe Bix', 'bix');