What is org.apache.jena.sdb.store.LayoutType?

[Ashwani Rathi]

Hi,
While creating a storeDesc, we need to pass in 
org.apache.jena.sdb.store.LayoutType as a parameter:

org.apache.jena.sdb.StoreDesc storeDesc = new 
org.apache.jena.sdb.StoreDesc(org.apache.jena.sdb.store.LayoutType layoutType,
                                org.apache.jena.sdb.store.DatabaseType 
databaseType) ; 


Does anyone knows what actually is this org.apache.jena.sdb.store.LayoutType? 
And how can we get this for an existing database?

Regards,
Ashwani