If insertion / deletion are the main operations, then probably
you should have a look at java.util.LinkedList. But the get() operation of a LinkedList is costly when compared to an ArrayList.
Ofcourse, Vector has an advantage - it is synchronized where as the ArrayList & LinkedList are not (that is the reason why Vector is slow). So, check whether you can afford to replace Vectors with LinkedList (or see whether using the synchronizedList method in Collections class will help, in that case).
[ February 01, 2006: Message edited by: Mani Ram ]