使用PowerMock-easymock模拟数据库对象

Question

I have an Interface ShoppingListDAO as below.

public interface ShoppingListDAO extends GenericDAO<Object, String> {       
    public List<ShoppingList> getShoppingList(Department department) throws ShoppingListDAOException;
}

And It's implementation DAO class is something like below one.

 public  class ShoppingListDAOImpl extends GenericCustomDAO<Object, String> implements ShoppingListDAO {
    //.......
    public  List<ShoppingList> getShoppingList(Department department)  throws ShoppingListDAOException {

    try {               
        ds = getDataSource();
        connection = ds.getConnection();

        callableStatment = connection.prepareCall(SHOPPING_LIST_QRY1);  
        callableStatment.setString(1, department.getDistributorNumber());
        //......    
        callableStatment.registerOutParameter(4, OracleTypes.CURSOR);

        callableStatment.execute();
        resultSet= (ResultSet) callableStatment.getObject(4);

        while(resultSet.next()) {
            //.......
        }           
    } catch (SQLException e) {          
        e.printStackTrace();
        throw new ShoppingListDAOException(e);
    } catch (Exception e) {         
        e.printStackTrace();
        throw new ShoppingListDAOException(e);
    }finally{
        //......                
    }   
}

    return shoppingList;
}

Now I have requirement to Test my implemented DAO class using Mock db Objects.I searched through POWERMOCK/EASYMOCK documentation but I guess most of the API methods provides me objects that provide me dummy implementation class of DAO interface.

1. is There some way i can create mock object of CONNECTION (assuming i don't have physical database access) and can run subsequent code provided in my ShoppingListDAOImpl class as i have to use this mocking for CODE COVERAGE purpose?

2. if there is any way i can make callableStatement.execute() to return Dummy data or Exception(withour physical database access) so that i can check it in my JUnit test cases?

I am quite new to mocking framework ,So may be my requirements are unrealistic. Any Information would be helpful.

Answer 1

With mock frameworks like EasyMock, Powermock or Mockito, you can mock everything. But I would not recommend to mock the Connection .

In your case, I would use an in-memory database like HSQLDB to test your DAO against a real DB but a DB which runs in-memory. This way, your test are not dependent of any external resources and can easily run on any environment.

By testing your code against a database, you are strictly not unit testing it anymore. Though I think this is an acceptable tradeoff.