Use this dialog box to specify options for the Use Supertype Where Possible refactoring command. You can use the Use Supertype Where Possible command to change code that references the selected class (or other type) so that it references a supertype of the selected type. Before replacing those references, the IDE checks to make sure that supertype and its members are accessible to all of the code that would be changed to reference them.
You can open the Use Supertype Where Possible dialog box by choosing Refactor > Use Supertype Where Possible after you have selected a class or other type in the Source Editor, Projects window, or Files window.
The dialog box has the following field:
If you want to preview the changes, you need to follow these steps to complete the refactoring:
The Refactoring window opens and displays a tree view of the code to be affected by the refactoring.