currentUpgrader = addUpgrader(currentUpgrader, new Version1Upgrader());
case 2:
currentUpgrader = addUpgrader(currentUpgrader, new Version2Upgrader());
case CURRENT_CONFIG_VERSION:
currentUpgrader = addUpgrader(currentUpgrader, new NullUpgrader(recoverer));
break;
default:
throw new IllegalStateException("Unknown configuration model version: " + configVersion
+ ". Attempting to run an older instance against an upgraded configuration?");