@Override
  public ReusableGetAdaptor createGetter(MapJoinKey keyTypeFromLoader) {
    if (keyTypeFromLoader != null) {
      throw new AssertionError("No key expected from loader but got " + keyTypeFromLoader);
    }
    return new GetAdaptor();
  }
Gets the partition Id into which to spill the big table row
@return partition Id
ql/src/java/org/apache/hadoop/hive/ql/exec/persistence/HybridHashTableContainer.java