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Java / Java 21 Collection Framework features Interview questions

Describe the sequencedKeySet(), sequencedValues(), and sequencedEntrySet() methods?

These three methods on SequencedMap return ordered, sequenced views of the map's keys, values, and entries - counterparts to the plain keySet(), values(), and entrySet() from Map.

MethodReturns
sequencedKeySet()A SequencedSet<K> of the keys, in encounter order
sequencedValues()A SequencedCollection<V> of the values, in encounter order
sequencedEntrySet()A SequencedSet<Entry<K,V>> of the entries, in encounter order

Because the results are sequenced types, you can call getFirst(), getLast(), or reversed() directly on them, which the plain keySet()/values()/entrySet() views don't support.

sequencedKeySet() returns a:
An advantage of sequencedEntrySet() over entrySet() is that you can:

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