• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 182
  • Last Modified:

Colloection choice, which one is best for my problem

I have been studing the collection material I could find on the webulator, My problem is as follows;

1, Class a (customers) containd a Cust_ID String and a customer name.
2, Class b (SalesOrder) contains details of sales orders including Cust_ID which has a one to many relationship with class a

I would like to create a data structure which contains both sets of data with class a as the key and class b as the

I would like to be able to retrieve multiple instances of class b dependant on a value of class a.  I also want that class b is retrieved in a particular sequence (Document number)

I have looked at MAPs   but they want unique values.

I do not want anyone to write the code ,just a nudge in the right direction, I'm thinking TreeSets. Examples of code pertaining to nudging however will not be frowned upon.
1 Solution
You need

Map<ClassA, List<ClassB>>;
> I also want that class b is retrieved in a particular sequence (Document number)
Use TreeSet or PriorityQueue for bs
i'd go with:

Map<A, TreeSet<B>>;

make B implement Comparable ordering by doc number

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now