@RequiresSession
  public AlertTargetEntity findTargetById(long targetId) {
    return entityManagerProvider.get().find(AlertTargetEntity.class, targetId);
  }
Gets an alert target with the specified ID.

@param targetId
         the ID of the target to retrieve.
@return the target or {@code null} if none exists.
ambari-server/src/main/java/org/apache/ambari/server/orm/dao/AlertDispatchDAO.java