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1
52
53 package freemarker.ext.dom;
54
55 import freemarker.template.*;
56 import freemarker.template.utility.Collections12;
57 import freemarker.template.utility.UndeclaredThrowableException;
58 import freemarker.cache.TemplateCache;
59 import freemarker.core.CustomAttribute;
60 import freemarker.core.Environment;
61 import org.jaxen.*;
62 import org.jaxen.dom.DocumentNavigator;
63 import org.w3c.dom.Document  ;
64 import org.xml.sax.EntityResolver ;
65 import org.xml.sax.InputSource ;
66 import org.xml.sax.SAXException ;
67
68 import java.io.IOException ;
69 import java.io.StringReader ;
70 import java.io.StringWriter ;
71 import java.util.*;
72
73 import javax.xml.parsers.DocumentBuilder ;
74 import javax.xml.parsers.DocumentBuilderFactory ;
75
76
77
81 class JaxenXPathSupport implements XPathSupport {
82
83 private static final CustomAttribute cache =
84 new CustomAttribute(CustomAttribute.SCOPE_TEMPLATE) {
85 protected Object create() {
86 return new HashMap();
87 }
88 };
89
90 private final static ArrayList EMPTY_ARRAYLIST = new ArrayList();
91
92 public TemplateModel executeQuery(Object context, String xpathQuery) throws TemplateModelException {
93 try {
94 BaseXPath xpath;
95 Map xpathCache = (Map)cache.get();
96 synchronized(xpathCache) {
97 xpath = (BaseXPath) xpathCache.get(xpathQuery);
98 if (xpath == null) {
99 xpath = new BaseXPath(xpathQuery, fmDomNavigator);
100 xpath.setNamespaceContext(customNamespaceContext);
101 xpath.setFunctionContext(fmFunctionContext);
102 xpath.setVariableContext(fmVariableContext);
103 xpathCache.put(xpathQuery, xpath);
104 }
105 }
106 List result = xpath.selectNodes(context != null ? context : EMPTY_ARRAYLIST);
107 if (result.size() == 1) {
108 return ObjectWrapper.DEFAULT_WRAPPER.wrap(result.get(0));
109 }
110 NodeListModel nlm = new NodeListModel(result, null);
111 nlm.xpathSupport = this;
112 return nlm;
113 } catch (UndeclaredThrowableException e) {
114 Throwable t = e.getUndeclaredThrowable();
115 if(t instanceof TemplateModelException) {
116 throw (TemplateModelException)t;
117 }
118 throw e;
119 } catch (JaxenException je) {
120 throw new TemplateModelException(je);
121 }
122 }
123
124 static private final NamespaceContext customNamespaceContext = new NamespaceContext() {
125
126 public String translateNamespacePrefixToUri(String prefix) {
127 if (prefix.equals(Template.DEFAULT_NAMESPACE_PREFIX)) {
128 return Environment.getCurrentEnvironment().getDefaultNS();
129 }
130 return Environment.getCurrentEnvironment().getNamespaceForPrefix(prefix);
131 }
132 };
133
134 private static final VariableContext fmVariableContext = new VariableContext() {
135 public Object getVariableValue(String namespaceURI, String prefix, String localName)
136 throws
137 UnresolvableException
138 {
139 try {
140 TemplateModel model = Environment.getCurrentEnvironment().getVariable(localName);
141 if(model == null) {
142 throw new UnresolvableException("Variable " + localName + " not found.");
143 }
144 if(model instanceof TemplateScalarModel) {
145 return ((TemplateScalarModel)model).getAsString();
146 }
147 if(model instanceof TemplateNumberModel) {
148 return ((TemplateNumberModel)model).getAsNumber();
149 }
150 if(model instanceof TemplateDateModel) {
151 return ((TemplateDateModel)model).getAsDate();
152 }
153 if(model instanceof TemplateBooleanModel) {
154 return ((TemplateBooleanModel)model).getAsBoolean() ? Boolean.TRUE : Boolean.FALSE;
155 }
156 }
157 catch(TemplateModelException e) {
158 throw new UndeclaredThrowableException(e);
159 }
160 throw new UnresolvableException("Variable " + localName + " is not a string, number, date, or boolean");
161 }
162 };
163
164 private static final FunctionContext fmFunctionContext = new XPathFunctionContext() {
165 public Function getFunction(String namespaceURI, String prefix, String localName)
166 throws UnresolvableException {
167 try {
168 return super.getFunction(namespaceURI, prefix, localName);
169 }
170 catch(UnresolvableException e) {
171 return super.getFunction(null, null, localName);
172 }
173 }
174 };
175
176 private static final CustomAttribute cachedTree = new CustomAttribute(CustomAttribute.SCOPE_TEMPLATE);
177
178 private static final Navigator fmDomNavigator = new DocumentNavigator() {
179 public Object getDocument(String uri) throws FunctionCallException
180 {
181 try
182 {
183 Template raw = getTemplate(uri);
184 Document doc = (Document )cachedTree.get(raw);
185 if(doc == null) {
186 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
187 factory.setNamespaceAware(true);
188 DocumentBuilder builder = factory.newDocumentBuilder();
189 FmEntityResolver er = new FmEntityResolver();
190 builder.setEntityResolver(er);
191 doc = builder.parse(createInputSource(null, raw));
192 if(er.getCallCount() == 0) {
195 cachedTree.set(doc, raw);
196 }
197 }
198 return doc;
199 }
200 catch (Exception e)
201 {
202 throw new FunctionCallException("Failed to parse document for URI: " + uri, e);
203 }
204 }
205 };
206
207 static Template getTemplate(String systemId) throws IOException {
208 Environment env = Environment.getCurrentEnvironment();
209 String encoding = env.getTemplate().getEncoding();
210 if (encoding == null) {
211 encoding = env.getConfiguration().getEncoding(env.getLocale());
212 }
213 String templatePath = env.getTemplate().getName();
214 int lastSlash = templatePath.lastIndexOf('/');
215 templatePath = lastSlash == -1 ? "" : templatePath.substring(0, lastSlash + 1);
216 systemId = TemplateCache.getFullTemplatePath(env, templatePath, systemId);
217 Template raw = env.getConfiguration().getTemplate(systemId, env.getLocale(), encoding, false);
218 return raw;
219 }
220
221 private static InputSource createInputSource(String publicId, Template raw) throws IOException , SAXException {
222 StringWriter sw = new StringWriter ();
223 try {
224 raw.process(Collections12.EMPTY_MAP, sw);
225 }
226 catch(TemplateException e) {
227 throw new SAXException (e);
228 }
229 InputSource is = new InputSource ();
230 is.setPublicId(publicId);
231 is.setSystemId(raw.getName());
232 is.setCharacterStream(new StringReader (sw.toString()));
233 return is;
234 }
235
236 private static class FmEntityResolver implements EntityResolver {
237 private int callCount = 0;
238
239 public InputSource resolveEntity(String publicId, String systemId)
240 throws SAXException , IOException {
241 ++callCount;
242 return createInputSource(publicId, getTemplate(systemId));
243 }
244
245 int getCallCount() {
246 return callCount;
247 }
248 };
249 }
250 |
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