Doma 改善案。 汎用的なDelegateで論理削除。

DeleteDelegate.java

package tutorial.dao;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

import org.seasar.doma.jdbc.Config;

public class DeleteDelegate {

    protected final Config config;
    protected final Object dao;

    // DaoをObject型で受ける
    public DeleteDelegate(Config config, Object dao) {
        this.config = config;
        this.dao = dao;
    }

    // EntityをObject型で受ける
    public int delete(Object entity) {
        try {
            Field f = entity.getClass().getDeclaredField("deleteFlag");
            f.setAccessible(true);
            f.set(entity, true);
            Method m = dao.getClass().getMethod("update", entity.getClass());
            return (Integer) m.invoke(dao, entity);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

}

EmployeeDao.java

package tutorial.dao;

import org.seasar.doma.Dao;
import org.seasar.doma.Delegate;
import org.seasar.doma.Select;
import org.seasar.doma.Update;

import tutorial.AppConfig;
import tutorial.entity.Employee;

@Dao(config = AppConfig.class)
public interface EmployeeDao {

    @Select
    Employee selectById(int id);

    @Delegate(to = DeleteDelegate.class)
    int delete(Employee employee);

    @Update
    int update(Employee employee);
}