code: @Path("users")
      public DirectoryResource<User, APIUser> getUserDirectoryResource()
              throws GuacamoleException {
          return userDirectoryResourceFactory.create(userContext,
                  userContext.getUserDirectory());
      }
docs: Returns a new resource which represents the User Directory contained
  within the UserContext exposed by this UserContextResource.
  
  @return
  A new resource which represents the User Directory contained within
  the UserContext exposed by this UserContextResource.
  
  @throws GuacamoleException
  If an error occurs while retrieving the User Directory.