| Operations | Time Complexity | Notes |
| get, put | O(1) | assuming the hash function has dispersed the elements properly among the buckets |
| iteration over collection views | proportional to the capacity plus the size | do not set the initial capacity too high or the load factor too low |
- Making no guarantees to the iteration order and the constantness of the order over time either.
- Unsynchronized and permitting nulls(both for key and value)
- 未完待续