Hi Prithvi,
Since you mentioned MyEclipse, you may want to take a look at the new GWT generation capability in MyEclipse for Spring 8.6. It doesn't have EXT yet, but does generate a full CRUD GWT app based on either
java beans, jpa entities, or db tables - and could give you a lot of good help when trying to create GWT.
Here's a couple helpful links:
GWT MyEclipse Tutorial:
http://www.dzone.com/links/r/tutorial_scaffold_a_spring_gwt_app_in_minutes.html
GWT Scaffolding Tips Video:
http://www.youtube.com/watch?v=4tKGvbxk1-Y
HTH!
Dave