What are the differences between HashSet and TreeSet in Java?

What are the differences between HashSet and TreeSet in Java?

HashSet is an unordered collection that allows null values, while TreeSet is a sorted collection that does not allow nulls.

Can you explain how they handle duplicates?

Both HashSet and TreeSet do not allow duplicate elements. However, HashSet uses hash codes for checking duplicates, while TreeSet uses the compareTo method.

Which one is more efficient for large datasets?

HashSet is generally more efficient for large datasets due to its O(1) time complexity for add, remove, and contains operations, compared to TreeSet's O(log n).

When should I use TreeSet instead of HashSet?

Use TreeSet when you need a sorted collection or when you need to perform range queries, as it maintains order.

Are there any performance trade-offs I should be aware of?

Yes, while HashSet is faster for basic operations, TreeSet has overhead due to maintaining order, which can affect performance.