Question on doing things the "Flat" way

[Rick <ri...@gmail.com>]

I was going to mail this directly to a few of my buds, but figured
whatever the response is, it could be useful for others...

First the business requirements:
//hypothetical example for sake of this email:

1) Show a single person and their favorite cars and display the
person's rank of each car

2) Show multiple persons and their favorite cars and for each person
display the person's rank of their cars

The data model looks like:

Person
---------
id
name
//etc


Car
-----
id
name
make
color
//etc


Person_Car
--------------
person_id
car_id
Integer rank



So how do you guys  like to set up you value objects to represent the
scenarios in 1 and 2?

Some of you I know wouldn't like to have a
Collection<Car> favoriteCars in the Person object

Also, what do you do about the "Integer rank?"

Since "rank" is only one field, I'd consider adding it as a property
on Car. If there were a lot of properties (like imagine Date rankDate
, etc.) I might make a "CarRank" value object. Lets say you had the
latter (a "CarRank" object) - for you guys that do things flat how do
you return your object graph?  Would you return a Map with Person as
key, and the value as a List of Maps where "Car" is key and "CarRank"
object as value?

I tend to think in terms of adding collections to my objects as
properties, so this 'flat' concept is new to me, but I really want to
nail down this "flat" way of thinking so I can consider using it
myself.

Thanks for any feedback.

Re: Question on doing things the "Flat" way

[Clinton Begin <cl...@gmail.com>]

I'd use 3 separate classes whether it was flat or not:  Person, Car,
CarRanking

I'd add the collection (and the back reference) as necessary (i.e. where it
made sense for my application).

Clinton

On Sat, Nov 15, 2008 at 6:43 AM, Rick <ri...@gmail.com> wrote:

> I was going to mail this directly to a few of my buds, but figured
> whatever the response is, it could be useful for others...
>
> First the business requirements:
> //hypothetical example for sake of this email:
>
> 1) Show a single person and their favorite cars and display the
> person's rank of each car
>
> 2) Show multiple persons and their favorite cars and for each person
> display the person's rank of their cars
>
> The data model looks like:
>
> Person
> ---------
> id
> name
> //etc
>
>
> Car
> -----
> id
> name
> make
> color
> //etc
>
>
> Person_Car
> --------------
> person_id
> car_id
> Integer rank
>
>
>
> So how do you guys  like to set up you value objects to represent the
> scenarios in 1 and 2?
>
> Some of you I know wouldn't like to have a
> Collection<Car> favoriteCars in the Person object
>
> Also, what do you do about the "Integer rank?"
>
> Since "rank" is only one field, I'd consider adding it as a property
> on Car. If there were a lot of properties (like imagine Date rankDate
> , etc.) I might make a "CarRank" value object. Lets say you had the
> latter (a "CarRank" object) - for you guys that do things flat how do
> you return your object graph?  Would you return a Map with Person as
> key, and the value as a List of Maps where "Car" is key and "CarRank"
> object as value?
>
> I tend to think in terms of adding collections to my objects as
> properties, so this 'flat' concept is new to me, but I really want to
> nail down this "flat" way of thinking so I can consider using it
> myself.
>
> Thanks for any feedback.
>