Getting Startedwith pureQuery

Chapter 13 – Handlers 275
package hrm.inProgress;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import com.ibm.pdq.runtime.handlers.ParameterHandler;
public class SimpleSelectEmployeeParameterHandler implements
ParameterHandler
{
public void handleParameters (PreparedStatement stmt, Object...
parameters)
throws SQLException
{
System.out.println ("Using " +
SimpleSelectEmployeeParameterHandler.class.getCanonicalName () +
"!");
String employeeNumber = (String) parameters[0];
stmt.setString (1, employeeNumber);
}
}
Listing 13.21 - The implementation of SimpleSelectEmployeeParameterHandler
Now, we need to specify SimpleSelectEmployeeParameterHandler for the
selectEmployee method in
hrm.inProgress.pdqMethodStyleWithHandlers.HumanResourcesData.
Because the handler has an implicit public no-argument constructor, we can use the
@Handler annotation to specify the handler. Add the annotation to your method, providing
the class of the handler.
@Select(sql = "SELECT * FROM EMPLOYEE WHERE EMPNO = ?")
@Handler(parameterHandler = SimpleSelectEmployeeParameterHandler.class)
EmployeeBean selectEmployee (String employeeNumber);
Listing 13.22 - The selectEmployee method with
SimpleSelectEmployeeParameterHandler
Build the project to regenerate the implementation class and test the application. Look for
the message that SimpleSelectEmployeeParameterHandler prints.
13.5 Summary
pureQuery provides handlers through which you can customize how pureQuery sets the
values of SQL parameters and how it returns query results. Implementations of the
com.ibm.pdq.runtime.handlers.ParameterHandler interface customize how the
values of parameters are set. Implementations of the
com.ibm.pdq.runtime.handlers.ResultHandler interface customize the