Change in code structure, Vaadin 6 v/s Vaadin 7

General
1

Hi all,
I have a Vaadin 7 application program and I want to change it into the format of vaadin 6. So, When i making changes in the code, some problem are there. i need the alternatives of some code in vaadin 7 to use in vaadin 6.
1.View.
2.getSession() and getUI().
3.Contentmode.HTML.
4.Navigator.
5.VaadinService