Difference Between Arraylist And Vector In Java?

1.	Difference Between Arraylist And Vector In Java?
Answer» ARRAYLIST is not synchronized WHEREAS Vector is synchronized. Performance wise ArrayList is fast in comparison to Vector as ArrayList is not synchronized. ArrayList, by default, grows by 50% in case the initial capacity is EXHAUSTED. In case of Vector the backing array's size is doubled by default. For TRAVERSING an ArrayList iterator is used. For traversing Vecor Iterator/Enumerator can be used. NOTE that Iterator is fail-fast for both Vector and ArrayList. Enumerator which can be used with Vector is not fail-fast.

Answer»

ARRAYLIST is not synchronized WHEREAS Vector is synchronized.
Performance wise ArrayList is fast in comparison to Vector as ArrayList is not synchronized.
ArrayList, by default, grows by 50% in case the initial capacity is EXHAUSTED. In case of Vector the backing array's size is doubled by default.
For TRAVERSING an ArrayList iterator is used. For traversing Vecor Iterator/Enumerator can be used. NOTE that Iterator is fail-fast for both Vector and ArrayList. Enumerator which can be used with Vector is not fail-fast.

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