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1
7
8 package org.dom4j.xpath;
9
10 import java.io.Serializable  ;
11 import java.util.Collections ;
12 import java.util.Comparator ;
13 import java.util.HashMap ;
14 import java.util.HashSet ;
15 import java.util.Iterator ;
16 import java.util.List ;
17 import java.util.Map ;
18
19 import org.dom4j.InvalidXPathException;
20 import org.dom4j.Node;
21 import org.dom4j.NodeFilter;
22 import org.dom4j.XPathException;
23
24 import org.jaxen.FunctionContext;
25 import org.jaxen.JaxenException;
26 import org.jaxen.NamespaceContext;
27 import org.jaxen.SimpleNamespaceContext;
28 import org.jaxen.VariableContext;
29 import org.jaxen.XPath;
30 import org.jaxen.dom4j.Dom4jXPath;
31
32
41 public class DefaultXPath implements org.dom4j.XPath, NodeFilter, Serializable {
42 private String text;
43
44 private XPath xpath;
45
46 private NamespaceContext namespaceContext;
47
48
57 public DefaultXPath(String text) throws InvalidXPathException {
58 this.text = text;
59 this.xpath = parse(text);
60 }
61
62 public String toString() {
63 return "[XPath: " + xpath + "]";
64 }
65
66
68
73 public String getText() {
74 return text;
75 }
76
77 public FunctionContext getFunctionContext() {
78 return xpath.getFunctionContext();
79 }
80
81 public void setFunctionContext(FunctionContext functionContext) {
82 xpath.setFunctionContext(functionContext);
83 }
84
85 public NamespaceContext getNamespaceContext() {
86 return namespaceContext;
87 }
88
89 public void setNamespaceURIs(Map map) {
90 setNamespaceContext(new SimpleNamespaceContext(map));
91 }
92
93 public void setNamespaceContext(NamespaceContext namespaceContext) {
94 this.namespaceContext = namespaceContext;
95 xpath.setNamespaceContext(namespaceContext);
96 }
97
98 public VariableContext getVariableContext() {
99 return xpath.getVariableContext();
100 }
101
102 public void setVariableContext(VariableContext variableContext) {
103 xpath.setVariableContext(variableContext);
104 }
105
106 public Object evaluate(Object context) {
107 try {
108 setNSContext(context);
109
110 List answer = xpath.selectNodes(context);
111
112 if ((answer != null) && (answer.size() == 1)) {
113 return answer.get(0);
114 }
115
116 return answer;
117 } catch (JaxenException e) {
118 handleJaxenException(e);
119
120 return null;
121 }
122 }
123
124 public Object selectObject(Object context) {
125 return evaluate(context);
126 }
127
128 public List selectNodes(Object context) {
129 try {
130 setNSContext(context);
131
132 return xpath.selectNodes(context);
133 } catch (JaxenException e) {
134 handleJaxenException(e);
135
136 return Collections.EMPTY_LIST;
137 }
138 }
139
140 public List selectNodes(Object context, org.dom4j.XPath sortXPath) {
141 List answer = selectNodes(context);
142 sortXPath.sort(answer);
143
144 return answer;
145 }
146
147 public List selectNodes(Object context, org.dom4j.XPath sortXPath,
148 boolean distinct) {
149 List answer = selectNodes(context);
150 sortXPath.sort(answer, distinct);
151
152 return answer;
153 }
154
155 public Node selectSingleNode(Object context) {
156 try {
157 setNSContext(context);
158
159 Object answer = xpath.selectSingleNode(context);
160
161 if (answer instanceof Node) {
162 return (Node) answer;
163 }
164
165 if (answer == null) {
166 return null;
167 }
168
169 throw new XPathException("The result of the XPath expression is "
170 + "not a Node. It was: " + answer + " of type: "
171 + answer.getClass().getName());
172 } catch (JaxenException e) {
173 handleJaxenException(e);
174
175 return null;
176 }
177 }
178
179 public String valueOf(Object context) {
180 try {
181 setNSContext(context);
182
183 return xpath.stringValueOf(context);
184 } catch (JaxenException e) {
185 handleJaxenException(e);
186
187 return "";
188 }
189 }
190
191 public Number numberValueOf(Object context) {
192 try {
193 setNSContext(context);
194
195 return xpath.numberValueOf(context);
196 } catch (JaxenException e) {
197 handleJaxenException(e);
198
199 return null;
200 }
201 }
202
203 public boolean booleanValueOf(Object context) {
204 try {
205 setNSContext(context);
206
207 return xpath.booleanValueOf(context);
208 } catch (JaxenException e) {
209 handleJaxenException(e);
210
211 return false;
212 }
213 }
214
215
224 public void sort(List list) {
225 sort(list, false);
226 }
227
228
240 public void sort(List list, boolean distinct) {
241 if ((list != null) && !list.isEmpty()) {
242 int size = list.size();
243 HashMap sortValues = new HashMap (size);
244
245 for (int i = 0; i < size; i++) {
246 Object object = list.get(i);
247
248 if (object instanceof Node) {
249 Node node = (Node) object;
250 Object expression = getCompareValue(node);
251 sortValues.put(node, expression);
252 }
253 }
254
255 sort(list, sortValues);
256
257 if (distinct) {
258 removeDuplicates(list, sortValues);
259 }
260 }
261 }
262
263 public boolean matches(Node node) {
264 try {
265 setNSContext(node);
266
267 List answer = xpath.selectNodes(node);
268
269 if ((answer != null) && (answer.size() > 0)) {
270 Object item = answer.get(0);
271
272 if (item instanceof Boolean ) {
273 return ((Boolean ) item).booleanValue();
274 }
275
276 return answer.contains(node);
277 }
278
279 return false;
280 } catch (JaxenException e) {
281 handleJaxenException(e);
282
283 return false;
284 }
285 }
286
287
295 protected void sort(List list, final Map sortValues) {
296 Collections.sort(list, new Comparator () {
297 public int compare(Object o1, Object o2) {
298 o1 = sortValues.get(o1);
299 o2 = sortValues.get(o2);
300
301 if (o1 == o2) {
302 return 0;
303 } else if (o1 instanceof Comparable ) {
304 Comparable c1 = (Comparable ) o1;
305
306 return c1.compareTo(o2);
307 } else if (o1 == null) {
308 return 1;
309 } else if (o2 == null) {
310 return -1;
311 } else {
312 return o1.equals(o2) ? 0 : (-1);
313 }
314 }
315 });
316 }
317
318
320
328 protected void removeDuplicates(List list, Map sortValues) {
329 HashSet distinctValues = new HashSet ();
331
332 for (Iterator iter = list.iterator(); iter.hasNext();) {
333 Object node = iter.next();
334 Object value = sortValues.get(node);
335
336 if (distinctValues.contains(value)) {
337 iter.remove();
338 } else {
339 distinctValues.add(value);
340 }
341 }
342 }
343
344
352 protected Object getCompareValue(Node node) {
353 return valueOf(node);
354 }
355
356 protected static XPath parse(String text) {
357 try {
358 return new Dom4jXPath(text);
359 } catch (JaxenException e) {
360 throw new InvalidXPathException(text, e.getMessage());
361 } catch (Throwable t) {
362 throw new InvalidXPathException(text, t);
363 }
364 }
365
366 protected void setNSContext(Object context) {
367 if (namespaceContext == null) {
368 xpath.setNamespaceContext(DefaultNamespaceContext.create(context));
369 }
370 }
371
372 protected void handleJaxenException(JaxenException exception)
373 throws XPathException {
374 throw new XPathException(text, exception);
375 }
376 }
377
378
414 |
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