1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
########################################################################
#
# File Name: TreeWalker.py
#
# Documentation: http://docs.4suite.com/4DOM/TreeWalker.py.html
#
"""
Tree Walker from DOM Level 2. Allows multi-directional iteration over nodes.
WWW: http://4suite.com/4DOM e-mail: support@4suite.com
Copyright (c) 2000 Fourthought Inc, USA. All Rights Reserved.
See http://4suite.com/COPYRIGHT for license and copyright information
"""
from NodeFilter import NodeFilter
from xml.dom import NoModificationAllowedErr
from xml.dom import NotSupportedErr
class TreeWalker:
def __init__(self, root, whatToShow, filter, expandEntityReferences):
self.__dict__['__root'] = root
self.__dict__['__whatToShow'] = whatToShow
self.__dict__['__filter'] = filter
self.__dict__['__expandEntityReferences'] = expandEntityReferences
self.__dict__['__currentNode'] = root
### Attribute Access Methods -- xxx.attr ###
def __getattr__(self, name):
attrFunc = self._readComputedAttrs.get(name)
if attrFunc:
return attrFunc(self)
def __setattr__(self, name, value):
#Make sure attribute is not read-only
if name in self.__class__._readOnlyAttrs:
raise NoModificationAllowedErr()
#If it's computed execute that function
attrFunc = self.__class__._writeComputedAttrs.get(name)
if attrFunc:
attrFunc(self, value)
#Otherwise, just set the attribute
else:
self.__dict__[name] = value
### Attribute Methods -- xxx._get_attr() ###
def _get_root(self):
return self.__dict__['__root']
def _get_filter(self):
return self.__dict__['__filter']
def _get_whatToShow(self):
return self.__dict__['__whatToShow']
def _get_expandEntityReferences(self):
return self.__dict__['__expandEntityReferences']
def _get_currentNode(self):
return self.__dict__['__currentNode']
def _set_currentNode(self, value):
if value == None:
raise NotSupportedErr()
self.__dict__['__currentNode'] = value
### Methods ###
def parentNode(self):
next_node = None
if self.__dict__['__currentNode'] != self.__dict__['__root']:
next_node = self.__dict__['__currentNode']._get_parentNode()
while next_node and next_node != self.__dict__['__root'] \
and not (self.__checkWhatToShow(next_node) \
and self.__checkFilter(next_node) == NodeFilter.FILTER_ACCEPT):
next_node = next_node._get_parentNode()
if next_node:
self.__dict__['__currentNode'] = next_node
return next_node
def firstChild(self):
next_node = None
if self.__checkFilter(self.__dict__['__currentNode']) != NodeFilter.FILTER_REJECT:
next_node = self.__dict__['__currentNode']._get_firstChild()
while next_node and not (self.__checkWhatToShow(next_node) \
and self.__checkFilter(next_node) == NodeFilter.FILTER_ACCEPT):
next_node = next_node._get_nextSibling()
if next_node:
self.__dict__['__currentNode'] = next_node
return next_node
def lastChild(self):
next_node = None
if self.__checkFilter(self.__dict__['__currentNode']) != NodeFilter.FILTER_REJECT:
next_node = self.__dict__['__currentNode']._get_lastChild()
while next_node and not (self.__checkWhatToShow(next_node) \
and self.__checkFilter(next_node) == NodeFilter.FILTER_ACCEPT):
next_node = next_node._get_previousSibling()
if next_node:
self.__dict__['__currentNode'] = next_node
return next_node
def previousSibling(self):
prev_node = None
if self.__dict__['__currentNode'] != self.__root:
prev_node = self.__dict__['__currentNode']._get_previousSibling()
while prev_node and not (self.__checkWhatToShow(prev_node) \
and self.__checkFilter(prev_node) == NodeFilter.FILTER_ACCEPT):
prev_node = prev_node._get_previousSibling()
if prev_node:
self.__dict__['__currentNode'] = prev_node
return prev_node
def nextSibling(self):
next_node = None
if self.__dict__['__currentNode'] != self.__root:
next_node = self.__dict__['__currentNode']._get_nextSibling()
while next_node and not (self.__checkWhatToShow(next_node) and self.__checkFilter(next_node) == NodeFilter.FILTER_ACCEPT):
next_node = next_node._get_nextSibling()
if next_node:
self.__dict__['__currentNode'] = next_node
return next_node
def nextNode(self):
next_node = self.__advance()
while next_node and not (self.__checkWhatToShow(next_node) and self.__checkFilter(next_node) == NodeFilter.FILTER_ACCEPT):
next_node = self.__advance()
return next_node
def previousNode(self):
prev_node = self.__regress()
while prev_node and not (self.__checkWhatToShow(prev_node) and self.__checkFilter(prev_node) == NodeFilter.FILTER_ACCEPT):
prev_node = self.__regress()
return prev_node
def __advance(self):
if self.firstChild():
return self.__dict__['__currentNode']
if self.nextSibling():
return self.__dict__['__currentNode']
if self.parentNode():
return self.nextSibling()
return None
def __regress(self):
if self.previousSibling():
self.lastChild()
return self.__dict__['__currentNode']
if self.parentNode():
return self.__dict__['__currentNode']
return None
def __checkWhatToShow(self, node):
show_bit = 1 << (node._get_nodeType() - 1)
return self.__dict__['__whatToShow'] & show_bit
def __checkFilter(self, node):
if self.__dict__['__filter']:
return self.__dict__['__filter'].acceptNode(node)
else:
return NodeFilter.FILTER_ACCEPT
### Attribute Access Mappings ###
_readComputedAttrs = {'root':_get_root,
'whatToShow':_get_whatToShow,
'filter':_get_filter,
'expandEntityReferences':_get_expandEntityReferences,
'currentNode':_get_currentNode
}
_writeComputedAttrs = {'currentNode': _set_currentNode
}
# Create the read-only list of attributes
_readOnlyAttrs = filter(lambda k,m=_writeComputedAttrs: not m.has_key(k),
_readComputedAttrs.keys())
|
