Better type safety in Java collections

Posted by Paul Tomblin on Stack Overflow See other posts from Stack Overflow or by Paul Tomblin
Published on 2010-03-25T13:55:44Z Indexed on 2010/03/25 14:03 UTC
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java

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collections

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typesafety

In my java coding, I often end up with several Map<String,Map<String,foo>> or Map<String,List<String>> and then I have trouble remembering which String is which key. I comment the declaration with //Map<capabiltyId,Map<groupId,foo>> or //Map<groupId,List<capabilityId>, but it's not the greatest solution. If String wasn't final, I would make new classes CapabilityId extends String and GroupId extends String, but I can't. Is there a better way to keep track of which thing is the key and maybe have the compiler enforce it?

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