@Override
  public ObjectInspector getObjectInspector() throws SerDeException {
    return cachedObjectInspector;
  }
Return an object inspector that can read through the object
that we return from deserialize(). To wit, that means we need
to return an ObjectInspector that can read HCatRecord, given
the type info for it during initialize(). This also means
that this method cannot and should not be called before initialize()
hcatalog/core/src/main/java/org/apache/hive/hcatalog/data/HCatRecordSerDe.java