@Override
  public ObjectInspector getObjectInspector() throws SerDeException {
    return inspector;
  }
This method gets called multiple times by Hive. On some invocations, the properties will be empty.
We need to detect when the properties are not empty to initialize the class variables.
jdbc-handler/src/main/java/org/apache/hive/storage/jdbc/JdbcSerDe.java