code: @DELETE
      @Path("/{token}")
      public void invalidateToken(@PathParam("token") String authToken)
              throws GuacamoleException {
  
          // Invalidate session, if it exists
          if (!authenticationService.destroyGuacamoleSession(authToken))
              throw new GuacamoleResourceNotFoundException("No such token.");
  
      }
docs: Invalidates a specific auth token, effectively logging out the associated
  user.
  
  @param authToken
  The token being invalidated.
  
  @throws GuacamoleException
  If the specified token does not exist.