I have a requirement wherein I have 2 GWT CellTable's on the same page.
Lets call them A and B.
I need to sort columns of B, depending on user sort activity on A.
Any pointers for implementation of the same will be appreciated.
I wouldn't be able to give you example code, because it's a while since I've been using GWT, but this sounds like a typical case for an observer pattern. Table B would register with table A and A would notify its observers when the user resorts the table. http://en.wikipedia.org/wiki/Observer_pattern
Since cell tables represent a big data set, sorting on that dataset should be happening server side in your code.
If you get and update on your cell table A set other sort parameters for your service on B and call an update on that service.