Java: Comparing two string arrays and removing elements that exist in both arrays

Question

This is mainly a performance questions. I have a master list of all users existing in a String array AllUids. I also have a list of all end dated users existing in a String

Answer 1

You can't "remove" elements from arrays. You can set them to null, but arrays are of fixed size.

You could use java.util.Set and removeAll to take one set away from another, but I'd prefer to use the Google Collections Library:

Set allUids = Sets.newHashSet("Joe", "Tom", "Dan",
                                      "Bill", "Hector", "Ron");
Set endUids = Sets.newHashSet("Dan", "Hector", "Ron");
Set activeUids = Sets.difference(allUids, endUids);

That has a more functional feel to it.