Replacing MetaCatUtil.debugMessage or MetaCatUtil.logMetacat call with logMetacat (private Logger object) call
Merging in changes made in branch 'dataaccess' by Jing Tao.
Add a field to this class.
Implement Comparator interface.
Add code to do get subtree nodes from db.
Change the debug level.
A new class to store info about sub tree.