How can I return the difference between two lists?

Question

I have two array lists e.g.

List a;
contains : 10/10/2014, 10/11/2016

List b;
contains : 10/10/2016

How can i do

Answer 1

You can convert them to Set collections, and perform a set difference operation on them.

Like this:

Set ad = new HashSet(a);
Set bd = new HashSet(b);
ad.removeAll(bd);