How to have a list that has two keys?

[elfin sable]

I am planning to create a string hashmap, and I want to fetch the record using either conn_id or user_id.

[unique harbor]

You can:

• Store the same record for each key if space isn't an issue.
• Store the same record's pointer for each key. Have a separate ArrayList of records. Convenient if you want to edit the records.
  I'd hope you can avoid this by converting conn_id to its user_id equivalent, though.

[abstract niche]

Use the adapted variant of the hashmap

Unsure how you’d make them hash to the same index though

[stark ridge]

Make two StringArrayHashMaps. Give one of them a void value, and instead use the index from that one to access the other one

you'll need to be careful to keep them both in sync, but that shouldn't be too hard