/** Testing version - in-memory but inefficient as it uses a copy-in/copy-out block manager as a RAM disk*/
static public ExtHash createMem(RecordFactory factory, int bucketSizeBytes )
{
BlockMgr mgr = BlockMgrFactory.createMem("ExtHash", bucketSizeBytes) ;
ExtHash eHash = new ExtHash(new PlainFileMem(), factory, mgr) ;
return eHash ;
}