private void snapshotActiveConf() {
    currentMetaVars = new HashMap<>(MetastoreConf.metaVars.length);
    for (ConfVars oneVar : MetastoreConf.metaVars) {
      currentMetaVars.put(oneVar.getVarname(), MetastoreConf.getAsString(conf, oneVar));
    }
  }
Swaps the first element of the metastoreUris array with a random element from the
remainder of the array.
standalone-metastore/metastore-common/src/main/java/org/apache/hadoop/hive/metastore/HiveMetaStoreClient.java