private GenericSnapshotManager<P> snapshotManager() throws Exception {
if (_nullSnapshotManager != null)
return _nullSnapshotManager;
PrevaylerDirectory directory = new PrevaylerDirectory(prevalenceDirectory());
if (!_snapshotSerializers.isEmpty())
return new GenericSnapshotManager<P>(_snapshotSerializers, _primarySnapshotSuffix, prevalentSystem(), directory, journalSerializer());
String snapshotSuffix = "snapshot";
JavaSerializer snapshotSerializer = new JavaSerializer();