object design

[hong ye]

Hi,
I have a question about object design. I want to create a "Item" class which belongs to different Categories and Subcategories.

My question is : do I need to create list of Categories and Subcategories inside to Item class and what is right approach?

Class Item {

String id;
List category = new ArrayList();
List subCategory = new ArrayList();

...

}

or

Class Item {

String id;
String category;
String subCategory;
....

}

which way is better?

Thanks

[srinivas srinivasmeenavalli]

it's depending on situation or datastructure.
For example one Item related to multiple Categories and Subcategories ( one to many relationship)
your first approach is better.

  Class Item { 

String id; 
List category = new ArrayList(); 
List subCategory = new ArrayList(); 

... 

}   

in other case if one Item related to a Category and Subcategory ( one to one relationship)
your second approach is better.

Class Item { 

String id; 
String category; 
String subCategory; 
.... 

}      

judge based on the requirement