[progress Communities] [progress Openedge Abl] Forum Post: Composition In Openedge Classes

[Johan Vergeer]

I have a question regarding the use of composition in OpenEdge classes. I come from a C# / Java background and it looks like OpenEdge takes a different approach here. We have a use case where an order should be added to the database. In C# (using Entity Framework) I would create some entities like Order, OrderLine and Customer The way the entity classes would be build is like this: class Order { public int OrderId {get; set; } public int CustomerId {get; set; } public virtual Customer Customer { get; set; } public virtual ICollection OrderLines {get; set; } } class Customer { public int CustomerId {get; set; } public virtual ICollection Orders { get; set; } } class OrderLine { public int OrderLineId {get; set; } public int OrderId { get; set; } public virtual Order Order {get; set; } } I have done several OpenEdge courses but am still trying to get all the pieces into the right place here. Like in the IntroToOOP course I can see that I would have to use an order temp-table with a CustomerObj field. And the Customer object would hold a temp-table containing all the customer info. But then what would I do with all the properties for Customer. When a property updates, that that would have to be changed in the Customer object and in the Customer temp-table. What I would like to do is just use a AddOrder() method in the Customer class to create a new order, and then do something like customerrder:AddOrderLine(). What would be the best way to accomplish this in OpenEdge?

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