The ArrayList is class from collection framework , recent arrivals on the scene. The package java.util has always contained some other collection. Some are superseded by the new collection types like Vector superseded by ArrayList. Even so, they are not depricated because they are in wide use in existing code and will continue to be used until programmers shift over to new types.
ArrayList will never supercede Vector because Vector is synchronized and ArrayList is not. Therefore if you have an situation with multiple threads / users hitting on the same list then you either need to use Vector or wrap ArrayList in something that IS synchronized.
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