/**
  * Get refactoring preview. Preview is tree of refactoring changes.
  *
  * @param refactoringSession the refactoring session.
  * @return refactoring preview tree
  * @throws RefactoringException when there are no corresponding refactoring session
  */
 @POST
 @Path("get/preview")
 @Produces("application/json")
 @Consumes("application/json")
 public RefactoringPreview getRefactoringPreview(RefactoringSession refactoringSession)
     throws RefactoringException {
   return manager.getRefactoringPreview(refactoringSession.getSessionId());
 }