java - Mapping a JDBC ResultSet to an object

Question

I have a user class that has 16 attributes, things such as firstname, lastname, dob, username, password etc... These are all stored in a MySQL database and when I want to retrieve users I use a ResultSet. I want to map each of the columns back to the user attributes but the way I am doing it seems terribly inefficient. For example I am doing:

//ResultSet rs;
while(rs.next()) {
   String uid = rs.getString("UserId");
   String fname = rs.getString("FirstName");
   ...
   ...
   ...
   User u = new User(uid,fname,...);
   //ArrayList<User> users 
   users.add(u);
} 

i.e I retrieve all the columns and then create user objects by inserting all the column values into the User constructor.

Does anyone know of a faster, neater, way of doing this?

question from:https://stackoverflow.com/questions/21956042/mapping-a-jdbc-resultset-to-an-object

Answer 1

If you don't want to use any JPA provider such as OpenJPA or Hibernate, you can just give Apache DbUtils a try.

http://commons.apache.org/proper/commons-dbutils/examples.html

Then your code will look like this:

QueryRunner run = new QueryRunner(dataSource);

// Use the BeanListHandler implementation to convert all
// ResultSet rows into a List of Person JavaBeans.
ResultSetHandler<List<Person>> h = new BeanListHandler<Person>(Person.class);

// Execute the SQL statement and return the results in a List of
// Person objects generated by the BeanListHandler.
List<Person> persons = run.query("SELECT * FROM Person", h);