public void setRole(ProxyPentahoRole role) {
   userAssignmentsModified = false;
   this.role = role;
   if (role != null) {
     ArrayList<ProxyPentahoUser> unassignedUsers = new ArrayList<ProxyPentahoUser>();
     unassignedUsers.addAll(Arrays.asList(UserAndRoleMgmtService.instance().getUsers()));
     ArrayList<ProxyPentahoUser> assignedUsers = new ArrayList<ProxyPentahoUser>();
     assignedUsers.addAll(Arrays.asList(UserAndRoleMgmtService.instance().getUsers(role)));
     unassignedUsers.removeAll(assignedUsers);
     availableUsersList.setObjects(unassignedUsers);
     accumulatedUsersList.setObjects(assignedUsers);
   } else {
     List<ProxyPentahoUser> emptyList = Collections.emptyList();
     availableUsersList.setObjects(emptyList);
     accumulatedUsersList.setObjects(emptyList);
   }
 }
 public void refresh() {
   List<ProxyPentahoUser> userList = Arrays.asList(UserAndRoleMgmtService.instance().getUsers());
   usersList.setObjects(userList);
   userSelectionChanged();
 }