Source Code for Module AccessEngine.AEWalkers.Base

 1  ''' 
 2  Defines an abstract base class acting as an interface for all walkers. Defines 
 3  the methods to be provided. 
 4   
 5  @author: Peter Parente 
 6  @organization: IBM Corporation 
 7  @copyright: Copyright (c) 2005, 2007 IBM Corporation 
 8  @license: The BSD License 
 9   
10  All rights reserved. This program and the accompanying materials are made 
11  available under the terms of the BSD license which accompanies 
12  this distribution, and is available at 
13  U{http://www.opensource.org/licenses/bsd-license.php} 
14  ''' 
15   
16 -class AEWalker(object): 
17    '''     
18    Walks accessible hiearchy in a well-defined order determined by a subclass of 
19    this base class. The traversal is stateless so that the walker can begin at 
20    any node in the tree and walk in any direction. 
21     
22    @ivar por: The starting L{AEPor} for the L{AEWalker} 
23    @type por: L{AEPor} 
24    ''' 
25 -  def __init__(self, por): 
26      ''' 
27      Stores the starting L{AEPor}. 
28       
29      @param por: The current L{AEPor} for the L{AEWalker} 
30      @type por: L{AEPor} 
31      ''' 
32      self.por = por 
33       
34 -  def getCurrPOR(self): 
35      ''' 
36      @return: Point of regard to the current object 
37      @rtype: L{AEPor} 
38      @raise NotImplementedError: When not overriden in a subclass 
39      ''' 
40      return self.por 
41     
42 -  def getParentPOR(self): 
43      ''' 
44      @return: Point of regard to the parent of the current object 
45      @rtype: L{AEPor} 
46      @raise NotImplementedError: When not overriden in a subclass 
47      ''' 
48      raise NotImplementedError 
49     
50 -  def getNextPOR(self): 
51      ''' 
52      @return: Point of regard to the next object in the walk order 
53      @rtype: L{AEPor} 
54      @raise NotImplementedError: When not overriden in a subclass 
55      ''' 
56      raise NotImplementedError 
57     
58 -  def getPrevPOR(self): 
59      ''' 
60      @return: Point of regard to the previous object in the walk order 
61      @rtype: L{AEPor} 
62      @raise NotImplementedError: When not overriden in a subclass 
63      ''' 
64      raise NotImplementedError 
65     
66 -  def getFirstPOR(self): 
67      ''' 
68      @return: Point of regard to the first of all objects 
69      @rtype: L{AEPor} 
70      @raise NotImplementedError: When not overriden in a subclass 
71      ''' 
72      raise NotImplementedError 
73   
74 -  def getLastPOR(self): 
75      ''' 
76      @return: Point of regard to the last of all objects 
77      @rtype: L{AEPor} 
78      @raise NotImplementedError: When not overriden in a subclass 
79      ''' 
80      raise NotImplementedError 
81