Data Structure

[none_none]

Hello everyone! I am having problems designing a data structure that keeps track of the dollar amount of purchases made by those clients that have regular accounts which are numbered 0, 1, .... n. In the problem one does not know in advance how many purchases each account will have. There are some that have one or two purchases while others have 50. Does anyone have any idea on how to design this data structure? If anyone can assist me I would appreciate it much. Thanks!

[sjalle]

You must make yourself a Client class and an Account class. The Client class can then
store all the Client's Accounts in an internal ArrayList.

[none_none]

Do you have any suggestions of the methods that could be in each class. Where should the array be declared?

[sjalle]

As a see it you should have an addtional litle class: Purchase

class Purchase {
int transactNo;
double amount;
Date purchaseDate;
String description;
}

Client:

fields:
(clientNumber, name, addr ... blabla)
ArrayList accountList; // list of all accounts for Client

methods:
public void addAccount(Account acc);
public Account getAccount(int accNumber);
public void closeAccount(int accNumber);


Account:

fields:
(Client number, opened date.. blabla)
ArrayList purchaseList; // list of all purchases for account

methods:
public int addPuchase(Purchase aPurchase); // returns a system wide unique transaction number
public void listPurchases(Date fromDate, Date toDate);
public Purchase getPurchase(int transactNo);

[none_none]

Thank you man. I really appreciate your help. You have been of much help. I will work with what is provided and go from there. Thanks once more for the help.

[none_none]

I am still unable to figure out how to complete this data struture. Is there anyway that you can show me how you would go about completing a design like this one. I would be of great help if you could help me out. Thanks.