Using a Converter with non unique values

Vaadin 6 / 7 / 8 Framework Data Binding
1

I am trying to use a Converter to convert my values from a Model (id) to a Presentation (name). Since I am binding my data to a TextField, my Presentation must be a String. However, I run into the problem where the Presentation values are not unique. Such as:

 Id  Name
  2. John Smith
  3. John Smith

Now I can no long go from Presentation → Model.

Has anyone else run into this issue? Can I use CustomField<?> with a textfield to be able to convert from my Model to something other than String?

Here is an example for reference.

https://vaadin.com/wiki/-/wiki/Main/Creating%20your%20own%20converter%20for%20String%20-%20MyType%20conversion

2

I still have not found a solution for this. Is anyone using a database to pull primary key id’s where the values associated with these primary keys are not unique? Does the converter not handle this situation?

This is especially troublesome in a Table where each cell is represented as a String.

3

Is convertToPresentation always called before convertToModel? If this is the case then I can assign a currentId at the beginning of convertToPresentation and then just return that value in convertToModel.