Data Access - Spring Enterprise Recipes: A Problem Solution Approach - page 110

public Vehicle findByVehicleNo(String vehicleNo) {
String sql = "SELECT * FROM VEHICLE WHERE VEHICLE_NO = ?";
Vehicle vehicle = getSimpleJdbcTemplate().queryForObject(
sql, Vehicle.class, vehicleNo);
return vehicle;
}
}
Querying for Multiple Rows
Now let's see how to query for a result set with multiple rows. For example, suppose that you need a
findAll() method in the DAO interface to get all vehicles.
package com.apress.springenterpriserecipes.vehicle;
...
public interface VehicleDao {
...
public List<Vehicle> findAll();
}
Without the help of RowMapper , you can still call the queryForList() method and pass in a SQL
statement. The returned result will be a list of maps. Each map stores a row of the result set with the
column names as the keys.
package com.apress.springenterpriserecipes.vehicle;
...
import org.springframework.jdbc.core.JdbcTemplate;
public class JdbcVehicleDao implements VehicleDao {
...
public List<Vehicle> findAll() {
String sql = "SELECT * FROM VEHICLE";
JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
List<Vehicle> vehicles = new ArrayList<Vehicle>();
List<Map<String,Object>> rows = jdbcTemplate. queryForList(sql);
for (Map<String, Object> row : rows) {
Vehicle vehicle = new Vehicle();
vehicle.setVehicleNo((String) row.get("VEHICLE_NO"));
vehicle.setColor((String) row.get("COLOR"));
vehicle.setWheel((Integer) row.get("WHEEL"));
vehicle.setSeat((Integer) row.get("SEAT"));
vehicles.add(vehicle);
}
return vehicles;
}
}