[FELIX-5254] Improve structure of permutations to use unmodifiable capability lists

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: resolver-1.8.0
• Component/s: Resolver
• Environment: All
• Assignee: Tom Watson
• Reporter: Tom Watson
• Created: 11/May/16 18:06
• Updated: 31/May/16 21:42
• Resolved: 31/May/16 21:42

Description

As discussed on the felix dev mailing list:

Implement a capability selection collection that
points to a constant list of capabilities and has an index to the currently
selected candidate for that permutation. That way there is no copying of
the constant list, instead we have a super lightweight collection that
points to the unmodifiable list of capabilities and just has an index.
Changing a Permutation would only involve incrementing that index instead
of removing from a copy on write list. We can then get rid of duplicate
capability lists since the list is unmodifiable it can be shared with
multiple selection index lists.