DBException createXMLObject creates a new XMLObject object and any associated system resources that the XMLObject will need. DBObject isOpened returns whether or not the DBObject is opened for business. DBObject exists returns whether or not a physical representation of this DBObject actually exists. In the case of a HashFiler, this would check for the file, and in the case of an FTPFiler, it might perform a connection check. DBObject create creates a new DBObject and any associated resources for the new DBObject, such as disk files, etc.
DBObject drop instructs the DBObjectimplementation to remove itself from existence.
The DBObject's parent is responsible for removing any references to the DBObject in its own context.