Many-to-Many Relationship (with properties) in Google App Engine for Java

Posted by rvandervort on Stack Overflow See other posts from Stack Overflow or by rvandervort
Published on 2010-06-18T02:34:13Z Indexed on 2010/06/18 12:03 UTC
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java

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google-app-engine

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relationships

I understand from the official documentation on unowned relationships that the app must use sets of Key objects on either side of the relationship. This makes perfect sense.

Coming from many years of RDBM-style programming, though, I'm pretty confused about how I can model properties of that relationship itself. For example, if I have entities Category and Entry in my many-to-many relationship and would like to persist a dateAdded property, or some other data that are only relevant when both sides of the relationship are known.

I suppose it would be possible to create a third class : CategoryEntry that links the two, but this seems like a kludge.

What is the proposed way to model this kind of situation ?

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