private UpgradePack getUpgradePack(UpgradeEntity upgrade) {
    StackId stackId = upgrade.getUpgradePackStackId();

    Map<String, UpgradePack> packs = m_metaInfo.getUpgradePacks(
        stackId.getStackName(), stackId.getStackVersion());

    return packs.get(upgrade.getUpgradePackage());
  }
Loads the upgrade pack used for an upgrade after it has been persisted.

@param upgrade
         the upgrade entity
@return
         the upgrade pack.  May be {@code null} if it doesn't exist
ambari-server/src/main/java/org/apache/ambari/server/stack/upgrade/orchestrate/UpgradeContext.java