For your specific situation: (if I understand it correctly)Vector or Array of large/huge number of employees. Most the time, it is an almost sorted stuff with a few anomalies. The most efficient way to do it is write you own bubble sort routine. O(n) can be reached easily.
You hear me correctly,
bubble sort. The algorithm can be found from Sun's demo with JDK. You can
test and prove my "theory" easily by using Sun'a
applet. The first time you click Bubble sort first, then Quick sort. You will see quick sort is much faster than bubble sort. However, since it is already sorted, this time you click quick sort first, then bubble sort to see who wins.
Thanks!
Roseanne