Hi Larry,
I like your first solution and will adopt it. Thank you.
As for storing the userId inside the Address object, your point is
well-taken
and will work in this case since it is a m:1 relationship. However, in a
more
complex scenario say Student and Course, it would be incorrect for the
Course object to store a List of studentIds. I've extended this paradigm
and applied it (perhaps incorrectly) to User/Address. Maybe I need to
re-think my m:1 relationships so that programming the DAOs is easier.
Thanks for your help.
Zarar
----- Original Message -----
From: "Larry Meadors" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, June 14, 2005 10:22 AM
Subject: Re: Multiple Objects as parameters
you could do a couple of things:
1) Put both the use and address into a map:
Map params = new HashMap();
params.put("user", user);
params.put("address", address);
2) Create a bean for them:
class UserAddress{
private User user;
private Address address;
public void setUser(User u){this.user = u;}
public void setAddress(Address a){this.address = a;}
// etc..
}
In either case, you can refer to the parameter object the same way in
your sql map: userAddress.user.userId
Now, on a related note...if you have a userId in the database, why not
have it in the related bean? I am not sure I understand why you say
"It doesn't make sense for the Address object to store a UserId."
Because you are storing a userId...just in the database...and
disconnecting it artificially in your Java code. From what I can see,
that adds no value, and increases the complexity of the system
(unneccesarily).
Larry
On 6/14/05, Zarar Siddiqi <[EMAIL PROTECTED]> wrote:
Multiple Objects as parameters
Hi,
I've encountered a situation which I am sure most developers
have faced and resolved in their own way when using iBatis.
Consider the following scenario. We have two tables:
USER(UserId,Name,Age,Occupation)
ADDRESS(AddressId,UserId,Street,City,ZipCode,State,Country);
Pretty simple case. A user has multiple addresses.
It doesn't make sense for the Address object to store a UserId.
So, it looks like:
public class Address {
private String addressId, street, city, zipCode, state, country;
// more methods here
}
Now, when adding an Address, I also have to store the userId which I
have access to in my Java code but have no clear means of passing it
in via the SqlMapClient. So, the work around for me is:
// Get a new address
Address addr = RequestObjectFactory.getAddress(request);
// Copy fields of addr into a map
Map params = PropertyUtils.describe(addr);
// Add userId which is not present in addr
params.put("userId", new Integer(userId));
// Do insert
sqlMapClient.insert("addAddress", params);
The problem with the above code is that it relies on PropertyUtils
which I am assuming does some serious reflection to get the fields
of addr. This I want to avoid.
Is there a mechanism (or a better workaround) that allows for more
than one parameter to be passed into a query, in this case addr and
userId.
