Internal4 SourceCode GPL - https://github.com/iboxdb/db4o-gpl

All Known Implementing Classes:

ClientObjectContainer, Db4oDatabase, Entry, ExternalObjectContainer, IoAdaptedObjectContainer, LocalObjectContainer, No4, ObjectContainerBase, Rename, ReplicationRecord, StaticClass, StaticField, TransportObjectContainer, User
```
public interface Internal4
```
Marker interface to denote that a class is used for db4o internals.