public  void close() throws Exception
Finalize access to this user database.

 public Group createGroup(String groupname,
    String description)
Create and return a new Group  defined in this user database.

 public Role createRole(String rolename,
    String description)
Create and return a new Role  defined in this user database.

 public User createUser(String username,
    String password,
    String fullName)
Create and return a new User  defined in this user database.

 public Group findGroup(String groupname)
Return the Group  with the specified group name, if any;
otherwise return null.

 public Role findRole(String rolename)
Return the Role  with the specified role name, if any;
otherwise return null.

 public User findUser(String username)
Return the User  with the specified user name, if any;
otherwise return null.

 public Iterator getGroups()
Return the set of Group s defined in this user database.

 public String getId()
Return the unique global identifier of this user database.

 public Iterator getRoles()
Return the set of Role s defined in this user database.

 public Iterator getUsers()
Return the set of User s defined in this user database.

 public  void open() throws Exception
Initialize access to this user database.

 public  void removeGroup(Group group)
Remove the specified Group  from this user database.

 public  void removeRole(Role role)
Remove the specified Role  from this user database.

 public  void removeUser(User user)
Remove the specified User  from this user database.

 public  void save() throws Exception
Save any updated information to the persistent storage location for
this user database.