| Class | QueryState | Undocumented |
| Class | NumberQueryState | Create a new NumberQueryState object. |
| Class | StringQueryState | Create a new StringQueryState object. |
| Class | DateQueryState | Create a new DateQueryState object. |
| Class | DateIntervalQueryState | Create a new DateIntervalQueryState object. |
| Class | QueryExecuter | A QueryExecuter is responsible for taking the state (as in QueryState) |