@Override
  protected void publishChangeNotice() {
    // TODO: can optimize this by sending the account/container payload as the topic message,
    // so subscribers can update their cache and avoid the database query.
    super.publishChangeNotice();
  }
Get an existing container from a given account.
@param accountId the name of account which container belongs to.
@param containerId the id of container to get.
@return the requested {@link Container} object or null if not present.
@throws AccountServiceException if exception occurs when getting container.
ambry-account/src/main/java/com/github/ambry/account/CachedAccountService.java