private void deleteUsers(Set<UserRequest> requests)
      throws AmbariException {

    for (UserRequest r : requests) {
      String username = r.getUsername();
      if (!StringUtils.isEmpty(username)) {

        if (LOG.isDebugEnabled()) {
          LOG.debug("Received a delete user request, username= {}", username);
        }

        users.removeUser(users.getUserEntity(username));
      }
    }
  }
Deletes the users specified.

@param requests the users to delete
@throws AmbariException if the resources cannot be deleted
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UserResourceProvider.java