@Override
  public long getEstimatedMemorySize() {
    long size = 0;
    size += originalTableContainer == null ? 0 : originalTableContainer.getEstimatedMemorySize();
    size += (2 * JavaDataModel.get().object());
    return size;
  }
Root interface for a vector map join hash table (which could be a hash map, hash multi-set, or
hash set).
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/mapjoin/optimized/VectorMapJoinOptimizedHashTable.java