When should you choose SequencedMap over a regular Map?

Reach for SequencedMap - or code against it as the declared type - whenever the order entries were inserted (or the order they end up sorted in) genuinely matters to your logic, not just their key-value association.

Good fits include building a simple LRU-style cache with putFirst()/putLast() to track recency, processing a job queue where pollFirstEntry() pulls the oldest task, or displaying an ordered history where you need firstEntry()/lastEntry() without maintaining a separate list of keys.

If insertion order truly doesn't matter to your use case - say, a lookup table keyed by ID where any entry could be "first" without consequence - a plain Map (potentially backed by HashMap for speed) is simpler and often faster, since it avoids the bookkeeping LinkedHashMap does to maintain that order.

In short: declare SequencedMap when the API contract needs to promise ordered access; keep it as Map when order is an implementation detail nobody should rely on.