| <HTML> |
| <BODY BGCOLOR="white"> |
| <PRE> |
| <FONT color="green">001</FONT> /*<a name="line.1"></a> |
| <FONT color="green">002</FONT> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a> |
| <FONT color="green">003</FONT> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a> |
| <FONT color="green">004</FONT> * distributed with this work for additional information<a name="line.4"></a> |
| <FONT color="green">005</FONT> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a> |
| <FONT color="green">006</FONT> * to you under the Apache License, Version 2.0 (the "License");<a name="line.6"></a> |
| <FONT color="green">007</FONT> * you may not use this file except in compliance with the License.<a name="line.7"></a> |
| <FONT color="green">008</FONT> * You may obtain a copy of the License at<a name="line.8"></a> |
| <FONT color="green">009</FONT> *<a name="line.9"></a> |
| <FONT color="green">010</FONT> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a> |
| <FONT color="green">011</FONT> *<a name="line.11"></a> |
| <FONT color="green">012</FONT> * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a> |
| <FONT color="green">013</FONT> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a> |
| <FONT color="green">014</FONT> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a> |
| <FONT color="green">015</FONT> * See the License for the specific language governing permissions and<a name="line.15"></a> |
| <FONT color="green">016</FONT> * limitations under the License.<a name="line.16"></a> |
| <FONT color="green">017</FONT> */<a name="line.17"></a> |
| <FONT color="green">018</FONT> /*<a name="line.18"></a> |
| <FONT color="green">019</FONT> * $Id: CachedXPathAPI.java 524811 2007-04-02 15:51:59Z zongaro $<a name="line.19"></a> |
| <FONT color="green">020</FONT> */<a name="line.20"></a> |
| <FONT color="green">021</FONT> package org.apache.xpath;<a name="line.21"></a> |
| <FONT color="green">022</FONT> <a name="line.22"></a> |
| <FONT color="green">023</FONT> import javax.xml.transform.TransformerException;<a name="line.23"></a> |
| <FONT color="green">024</FONT> <a name="line.24"></a> |
| <FONT color="green">025</FONT> import org.apache.xml.utils.PrefixResolver;<a name="line.25"></a> |
| <FONT color="green">026</FONT> import org.apache.xml.utils.PrefixResolverDefault;<a name="line.26"></a> |
| <FONT color="green">027</FONT> import org.apache.xpath.objects.XObject;<a name="line.27"></a> |
| <FONT color="green">028</FONT> <a name="line.28"></a> |
| <FONT color="green">029</FONT> import org.w3c.dom.Document;<a name="line.29"></a> |
| <FONT color="green">030</FONT> import org.w3c.dom.Node;<a name="line.30"></a> |
| <FONT color="green">031</FONT> import org.w3c.dom.NodeList;<a name="line.31"></a> |
| <FONT color="green">032</FONT> import org.w3c.dom.traversal.NodeIterator;<a name="line.32"></a> |
| <FONT color="green">033</FONT> <a name="line.33"></a> |
| <FONT color="green">034</FONT> /**<a name="line.34"></a> |
| <FONT color="green">035</FONT> * The methods in this class are convenience methods into the<a name="line.35"></a> |
| <FONT color="green">036</FONT> * low-level XPath API.<a name="line.36"></a> |
| <FONT color="green">037</FONT> *<a name="line.37"></a> |
| <FONT color="green">038</FONT> * These functions tend to be a little slow, since a number of objects must be<a name="line.38"></a> |
| <FONT color="green">039</FONT> * created for each evaluation. A faster way is to precompile the<a name="line.39"></a> |
| <FONT color="green">040</FONT> * XPaths using the low-level API, and then just use the XPaths<a name="line.40"></a> |
| <FONT color="green">041</FONT> * over and over.<a name="line.41"></a> |
| <FONT color="green">042</FONT> *<a name="line.42"></a> |
| <FONT color="green">043</FONT> * This is an alternative for the old XPathAPI class, which provided<a name="line.43"></a> |
| <FONT color="green">044</FONT> * static methods for the purpose but had the drawback of<a name="line.44"></a> |
| <FONT color="green">045</FONT> * instantiating a new XPathContext (and thus building a new DTMManager,<a name="line.45"></a> |
| <FONT color="green">046</FONT> * and new DTMs) each time it was called. XPathAPIObject instead retains<a name="line.46"></a> |
| <FONT color="green">047</FONT> * its context as long as the object persists, reusing the DTMs. This<a name="line.47"></a> |
| <FONT color="green">048</FONT> * does have a downside: if you've changed your source document, you should<a name="line.48"></a> |
| <FONT color="green">049</FONT> * obtain a new XPathAPIObject to continue searching it, since trying to use<a name="line.49"></a> |
| <FONT color="green">050</FONT> * the old DTMs will probably yield bad results or malfunction outright... and<a name="line.50"></a> |
| <FONT color="green">051</FONT> * the cached DTMs may consume memory until this object and its context are<a name="line.51"></a> |
| <FONT color="green">052</FONT> * returned to the heap. Essentially, it's the caller's responsibility to<a name="line.52"></a> |
| <FONT color="green">053</FONT> * decide when to discard the cache.<a name="line.53"></a> |
| <FONT color="green">054</FONT> *<a name="line.54"></a> |
| <FONT color="green">055</FONT> * @see <a href="http://www.w3.org/TR/xpath">XPath Specification</a><a name="line.55"></a> |
| <FONT color="green">056</FONT> * */<a name="line.56"></a> |
| <FONT color="green">057</FONT> public class CachedXPathAPI<a name="line.57"></a> |
| <FONT color="green">058</FONT> {<a name="line.58"></a> |
| <FONT color="green">059</FONT> /** XPathContext, and thus the document model system (DTMs), persists through multiple<a name="line.59"></a> |
| <FONT color="green">060</FONT> calls to this object. This is set in the constructor.<a name="line.60"></a> |
| <FONT color="green">061</FONT> */<a name="line.61"></a> |
| <FONT color="green">062</FONT> protected XPathContext xpathSupport;<a name="line.62"></a> |
| <FONT color="green">063</FONT> <a name="line.63"></a> |
| <FONT color="green">064</FONT> /**<a name="line.64"></a> |
| <FONT color="green">065</FONT> * <p>Default constructor. Establishes its own {@link XPathContext}, and hence<a name="line.65"></a> |
| <FONT color="green">066</FONT> * its own {@link org.apache.xml.dtm.DTMManager}.<a name="line.66"></a> |
| <FONT color="green">067</FONT> * Good choice for simple uses.</p><a name="line.67"></a> |
| <FONT color="green">068</FONT> * <p>Note that any particular instance of {@link CachedXPathAPI} must not be<a name="line.68"></a> |
| <FONT color="green">069</FONT> * operated upon by multiple threads without synchronization; we do<a name="line.69"></a> |
| <FONT color="green">070</FONT> * not currently support multithreaded access to a single<a name="line.70"></a> |
| <FONT color="green">071</FONT> * {@link org.apache.xml.dtm.DTM}.</p><a name="line.71"></a> |
| <FONT color="green">072</FONT> */<a name="line.72"></a> |
| <FONT color="green">073</FONT> public CachedXPathAPI()<a name="line.73"></a> |
| <FONT color="green">074</FONT> {<a name="line.74"></a> |
| <FONT color="green">075</FONT> // Create an XPathContext that doesn't support pushing and popping of<a name="line.75"></a> |
| <FONT color="green">076</FONT> // variable resolution scopes. Sufficient for simple XPath 1.0 expressions.<a name="line.76"></a> |
| <FONT color="green">077</FONT> xpathSupport = new XPathContext(false);<a name="line.77"></a> |
| <FONT color="green">078</FONT> }<a name="line.78"></a> |
| <FONT color="green">079</FONT> <a name="line.79"></a> |
| <FONT color="green">080</FONT> /**<a name="line.80"></a> |
| <FONT color="green">081</FONT> * <p>This constructor shares its {@link XPathContext} with a pre-existing<a name="line.81"></a> |
| <FONT color="green">082</FONT> * {@link CachedXPathAPI}. That allows sharing document models<a name="line.82"></a> |
| <FONT color="green">083</FONT> * ({@link org.apache.xml.dtm.DTM}) and previously established location<a name="line.83"></a> |
| <FONT color="green">084</FONT> * state.</p><a name="line.84"></a> |
| <FONT color="green">085</FONT> * <p>Note that the original {@link CachedXPathAPI} and the new one should<a name="line.85"></a> |
| <FONT color="green">086</FONT> * not be operated upon concurrently; we do not support multithreaded access<a name="line.86"></a> |
| <FONT color="green">087</FONT> * to a single {@link org.apache.xml.dtm.DTM} at this time. Similarly,<a name="line.87"></a> |
| <FONT color="green">088</FONT> * any particular instance of {@link CachedXPathAPI} must not be operated<a name="line.88"></a> |
| <FONT color="green">089</FONT> * upon by multiple threads without synchronization.</p><a name="line.89"></a> |
| <FONT color="green">090</FONT> * <p>%REVIEW% Should this instead do a clone-and-reset on the XPathSupport object?</p><a name="line.90"></a> |
| <FONT color="green">091</FONT> *<a name="line.91"></a> |
| <FONT color="green">092</FONT> */<a name="line.92"></a> |
| <FONT color="green">093</FONT> public CachedXPathAPI(CachedXPathAPI priorXPathAPI)<a name="line.93"></a> |
| <FONT color="green">094</FONT> {<a name="line.94"></a> |
| <FONT color="green">095</FONT> xpathSupport = priorXPathAPI.xpathSupport;<a name="line.95"></a> |
| <FONT color="green">096</FONT> }<a name="line.96"></a> |
| <FONT color="green">097</FONT> <a name="line.97"></a> |
| <FONT color="green">098</FONT> <a name="line.98"></a> |
| <FONT color="green">099</FONT> /** Returns the XPathSupport object used in this CachedXPathAPI<a name="line.99"></a> |
| <FONT color="green">100</FONT> *<a name="line.100"></a> |
| <FONT color="green">101</FONT> * %REVIEW% I'm somewhat concerned about the loss of encapsulation<a name="line.101"></a> |
| <FONT color="green">102</FONT> * this causes, but the xml-security folks say they need it.<a name="line.102"></a> |
| <FONT color="green">103</FONT> * */<a name="line.103"></a> |
| <FONT color="green">104</FONT> public XPathContext getXPathContext()<a name="line.104"></a> |
| <FONT color="green">105</FONT> {<a name="line.105"></a> |
| <FONT color="green">106</FONT> return this.xpathSupport;<a name="line.106"></a> |
| <FONT color="green">107</FONT> }<a name="line.107"></a> |
| <FONT color="green">108</FONT> <a name="line.108"></a> |
| <FONT color="green">109</FONT> <a name="line.109"></a> |
| <FONT color="green">110</FONT> /**<a name="line.110"></a> |
| <FONT color="green">111</FONT> * Use an XPath string to select a single node. XPath namespace<a name="line.111"></a> |
| <FONT color="green">112</FONT> * prefixes are resolved from the context node, which may not<a name="line.112"></a> |
| <FONT color="green">113</FONT> * be what you want (see the next method).<a name="line.113"></a> |
| <FONT color="green">114</FONT> *<a name="line.114"></a> |
| <FONT color="green">115</FONT> * @param contextNode The node to start searching from.<a name="line.115"></a> |
| <FONT color="green">116</FONT> * @param str A valid XPath string.<a name="line.116"></a> |
| <FONT color="green">117</FONT> * @return The first node found that matches the XPath, or null.<a name="line.117"></a> |
| <FONT color="green">118</FONT> *<a name="line.118"></a> |
| <FONT color="green">119</FONT> * @throws TransformerException<a name="line.119"></a> |
| <FONT color="green">120</FONT> */<a name="line.120"></a> |
| <FONT color="green">121</FONT> public Node selectSingleNode(Node contextNode, String str)<a name="line.121"></a> |
| <FONT color="green">122</FONT> throws TransformerException<a name="line.122"></a> |
| <FONT color="green">123</FONT> {<a name="line.123"></a> |
| <FONT color="green">124</FONT> return selectSingleNode(contextNode, str, contextNode);<a name="line.124"></a> |
| <FONT color="green">125</FONT> }<a name="line.125"></a> |
| <FONT color="green">126</FONT> <a name="line.126"></a> |
| <FONT color="green">127</FONT> /**<a name="line.127"></a> |
| <FONT color="green">128</FONT> * Use an XPath string to select a single node.<a name="line.128"></a> |
| <FONT color="green">129</FONT> * XPath namespace prefixes are resolved from the namespaceNode.<a name="line.129"></a> |
| <FONT color="green">130</FONT> *<a name="line.130"></a> |
| <FONT color="green">131</FONT> * @param contextNode The node to start searching from.<a name="line.131"></a> |
| <FONT color="green">132</FONT> * @param str A valid XPath string.<a name="line.132"></a> |
| <FONT color="green">133</FONT> * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces.<a name="line.133"></a> |
| <FONT color="green">134</FONT> * @return The first node found that matches the XPath, or null.<a name="line.134"></a> |
| <FONT color="green">135</FONT> *<a name="line.135"></a> |
| <FONT color="green">136</FONT> * @throws TransformerException<a name="line.136"></a> |
| <FONT color="green">137</FONT> */<a name="line.137"></a> |
| <FONT color="green">138</FONT> public Node selectSingleNode(<a name="line.138"></a> |
| <FONT color="green">139</FONT> Node contextNode, String str, Node namespaceNode)<a name="line.139"></a> |
| <FONT color="green">140</FONT> throws TransformerException<a name="line.140"></a> |
| <FONT color="green">141</FONT> {<a name="line.141"></a> |
| <FONT color="green">142</FONT> <a name="line.142"></a> |
| <FONT color="green">143</FONT> // Have the XObject return its result as a NodeSetDTM.<a name="line.143"></a> |
| <FONT color="green">144</FONT> NodeIterator nl = selectNodeIterator(contextNode, str, namespaceNode);<a name="line.144"></a> |
| <FONT color="green">145</FONT> <a name="line.145"></a> |
| <FONT color="green">146</FONT> // Return the first node, or null<a name="line.146"></a> |
| <FONT color="green">147</FONT> return nl.nextNode();<a name="line.147"></a> |
| <FONT color="green">148</FONT> }<a name="line.148"></a> |
| <FONT color="green">149</FONT> <a name="line.149"></a> |
| <FONT color="green">150</FONT> /**<a name="line.150"></a> |
| <FONT color="green">151</FONT> * Use an XPath string to select a nodelist.<a name="line.151"></a> |
| <FONT color="green">152</FONT> * XPath namespace prefixes are resolved from the contextNode.<a name="line.152"></a> |
| <FONT color="green">153</FONT> *<a name="line.153"></a> |
| <FONT color="green">154</FONT> * @param contextNode The node to start searching from.<a name="line.154"></a> |
| <FONT color="green">155</FONT> * @param str A valid XPath string.<a name="line.155"></a> |
| <FONT color="green">156</FONT> * @return A NodeIterator, should never be null.<a name="line.156"></a> |
| <FONT color="green">157</FONT> *<a name="line.157"></a> |
| <FONT color="green">158</FONT> * @throws TransformerException<a name="line.158"></a> |
| <FONT color="green">159</FONT> */<a name="line.159"></a> |
| <FONT color="green">160</FONT> public NodeIterator selectNodeIterator(Node contextNode, String str)<a name="line.160"></a> |
| <FONT color="green">161</FONT> throws TransformerException<a name="line.161"></a> |
| <FONT color="green">162</FONT> {<a name="line.162"></a> |
| <FONT color="green">163</FONT> return selectNodeIterator(contextNode, str, contextNode);<a name="line.163"></a> |
| <FONT color="green">164</FONT> }<a name="line.164"></a> |
| <FONT color="green">165</FONT> <a name="line.165"></a> |
| <FONT color="green">166</FONT> /**<a name="line.166"></a> |
| <FONT color="green">167</FONT> * Use an XPath string to select a nodelist.<a name="line.167"></a> |
| <FONT color="green">168</FONT> * XPath namespace prefixes are resolved from the namespaceNode.<a name="line.168"></a> |
| <FONT color="green">169</FONT> *<a name="line.169"></a> |
| <FONT color="green">170</FONT> * @param contextNode The node to start searching from.<a name="line.170"></a> |
| <FONT color="green">171</FONT> * @param str A valid XPath string.<a name="line.171"></a> |
| <FONT color="green">172</FONT> * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces.<a name="line.172"></a> |
| <FONT color="green">173</FONT> * @return A NodeIterator, should never be null.<a name="line.173"></a> |
| <FONT color="green">174</FONT> *<a name="line.174"></a> |
| <FONT color="green">175</FONT> * @throws TransformerException<a name="line.175"></a> |
| <FONT color="green">176</FONT> */<a name="line.176"></a> |
| <FONT color="green">177</FONT> public NodeIterator selectNodeIterator(<a name="line.177"></a> |
| <FONT color="green">178</FONT> Node contextNode, String str, Node namespaceNode)<a name="line.178"></a> |
| <FONT color="green">179</FONT> throws TransformerException<a name="line.179"></a> |
| <FONT color="green">180</FONT> {<a name="line.180"></a> |
| <FONT color="green">181</FONT> <a name="line.181"></a> |
| <FONT color="green">182</FONT> // Execute the XPath, and have it return the result<a name="line.182"></a> |
| <FONT color="green">183</FONT> XObject list = eval(contextNode, str, namespaceNode);<a name="line.183"></a> |
| <FONT color="green">184</FONT> <a name="line.184"></a> |
| <FONT color="green">185</FONT> // Have the XObject return its result as a NodeSetDTM. <a name="line.185"></a> |
| <FONT color="green">186</FONT> return list.nodeset();<a name="line.186"></a> |
| <FONT color="green">187</FONT> }<a name="line.187"></a> |
| <FONT color="green">188</FONT> <a name="line.188"></a> |
| <FONT color="green">189</FONT> /**<a name="line.189"></a> |
| <FONT color="green">190</FONT> * Use an XPath string to select a nodelist.<a name="line.190"></a> |
| <FONT color="green">191</FONT> * XPath namespace prefixes are resolved from the contextNode.<a name="line.191"></a> |
| <FONT color="green">192</FONT> *<a name="line.192"></a> |
| <FONT color="green">193</FONT> * @param contextNode The node to start searching from.<a name="line.193"></a> |
| <FONT color="green">194</FONT> * @param str A valid XPath string.<a name="line.194"></a> |
| <FONT color="green">195</FONT> * @return A NodeIterator, should never be null.<a name="line.195"></a> |
| <FONT color="green">196</FONT> *<a name="line.196"></a> |
| <FONT color="green">197</FONT> * @throws TransformerException<a name="line.197"></a> |
| <FONT color="green">198</FONT> */<a name="line.198"></a> |
| <FONT color="green">199</FONT> public NodeList selectNodeList(Node contextNode, String str)<a name="line.199"></a> |
| <FONT color="green">200</FONT> throws TransformerException<a name="line.200"></a> |
| <FONT color="green">201</FONT> {<a name="line.201"></a> |
| <FONT color="green">202</FONT> return selectNodeList(contextNode, str, contextNode);<a name="line.202"></a> |
| <FONT color="green">203</FONT> }<a name="line.203"></a> |
| <FONT color="green">204</FONT> <a name="line.204"></a> |
| <FONT color="green">205</FONT> /**<a name="line.205"></a> |
| <FONT color="green">206</FONT> * Use an XPath string to select a nodelist.<a name="line.206"></a> |
| <FONT color="green">207</FONT> * XPath namespace prefixes are resolved from the namespaceNode.<a name="line.207"></a> |
| <FONT color="green">208</FONT> *<a name="line.208"></a> |
| <FONT color="green">209</FONT> * @param contextNode The node to start searching from.<a name="line.209"></a> |
| <FONT color="green">210</FONT> * @param str A valid XPath string.<a name="line.210"></a> |
| <FONT color="green">211</FONT> * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces.<a name="line.211"></a> |
| <FONT color="green">212</FONT> * @return A NodeIterator, should never be null.<a name="line.212"></a> |
| <FONT color="green">213</FONT> *<a name="line.213"></a> |
| <FONT color="green">214</FONT> * @throws TransformerException<a name="line.214"></a> |
| <FONT color="green">215</FONT> */<a name="line.215"></a> |
| <FONT color="green">216</FONT> public NodeList selectNodeList(<a name="line.216"></a> |
| <FONT color="green">217</FONT> Node contextNode, String str, Node namespaceNode)<a name="line.217"></a> |
| <FONT color="green">218</FONT> throws TransformerException<a name="line.218"></a> |
| <FONT color="green">219</FONT> {<a name="line.219"></a> |
| <FONT color="green">220</FONT> <a name="line.220"></a> |
| <FONT color="green">221</FONT> // Execute the XPath, and have it return the result<a name="line.221"></a> |
| <FONT color="green">222</FONT> XObject list = eval(contextNode, str, namespaceNode);<a name="line.222"></a> |
| <FONT color="green">223</FONT> <a name="line.223"></a> |
| <FONT color="green">224</FONT> // Return a NodeList.<a name="line.224"></a> |
| <FONT color="green">225</FONT> return list.nodelist();<a name="line.225"></a> |
| <FONT color="green">226</FONT> }<a name="line.226"></a> |
| <FONT color="green">227</FONT> <a name="line.227"></a> |
| <FONT color="green">228</FONT> /**<a name="line.228"></a> |
| <FONT color="green">229</FONT> * Evaluate XPath string to an XObject. Using this method,<a name="line.229"></a> |
| <FONT color="green">230</FONT> * XPath namespace prefixes will be resolved from the namespaceNode.<a name="line.230"></a> |
| <FONT color="green">231</FONT> * @param contextNode The node to start searching from.<a name="line.231"></a> |
| <FONT color="green">232</FONT> * @param str A valid XPath string.<a name="line.232"></a> |
| <FONT color="green">233</FONT> * @return An XObject, which can be used to obtain a string, number, nodelist, etc, should never be null.<a name="line.233"></a> |
| <FONT color="green">234</FONT> * @see org.apache.xpath.objects.XObject<a name="line.234"></a> |
| <FONT color="green">235</FONT> * @see org.apache.xpath.objects.XNull<a name="line.235"></a> |
| <FONT color="green">236</FONT> * @see org.apache.xpath.objects.XBoolean<a name="line.236"></a> |
| <FONT color="green">237</FONT> * @see org.apache.xpath.objects.XNumber<a name="line.237"></a> |
| <FONT color="green">238</FONT> * @see org.apache.xpath.objects.XString<a name="line.238"></a> |
| <FONT color="green">239</FONT> * @see org.apache.xpath.objects.XRTreeFrag<a name="line.239"></a> |
| <FONT color="green">240</FONT> *<a name="line.240"></a> |
| <FONT color="green">241</FONT> * @throws TransformerException<a name="line.241"></a> |
| <FONT color="green">242</FONT> */<a name="line.242"></a> |
| <FONT color="green">243</FONT> public XObject eval(Node contextNode, String str)<a name="line.243"></a> |
| <FONT color="green">244</FONT> throws TransformerException<a name="line.244"></a> |
| <FONT color="green">245</FONT> {<a name="line.245"></a> |
| <FONT color="green">246</FONT> return eval(contextNode, str, contextNode);<a name="line.246"></a> |
| <FONT color="green">247</FONT> }<a name="line.247"></a> |
| <FONT color="green">248</FONT> <a name="line.248"></a> |
| <FONT color="green">249</FONT> /**<a name="line.249"></a> |
| <FONT color="green">250</FONT> * Evaluate XPath string to an XObject. <a name="line.250"></a> |
| <FONT color="green">251</FONT> * XPath namespace prefixes are resolved from the namespaceNode.<a name="line.251"></a> |
| <FONT color="green">252</FONT> * The implementation of this is a little slow, since it creates<a name="line.252"></a> |
| <FONT color="green">253</FONT> * a number of objects each time it is called. This could be optimized<a name="line.253"></a> |
| <FONT color="green">254</FONT> * to keep the same objects around, but then thread-safety issues would arise.<a name="line.254"></a> |
| <FONT color="green">255</FONT> *<a name="line.255"></a> |
| <FONT color="green">256</FONT> * @param contextNode The node to start searching from.<a name="line.256"></a> |
| <FONT color="green">257</FONT> * @param str A valid XPath string.<a name="line.257"></a> |
| <FONT color="green">258</FONT> * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces.<a name="line.258"></a> |
| <FONT color="green">259</FONT> * @return An XObject, which can be used to obtain a string, number, nodelist, etc, should never be null.<a name="line.259"></a> |
| <FONT color="green">260</FONT> * @see org.apache.xpath.objects.XObject<a name="line.260"></a> |
| <FONT color="green">261</FONT> * @see org.apache.xpath.objects.XNull<a name="line.261"></a> |
| <FONT color="green">262</FONT> * @see org.apache.xpath.objects.XBoolean<a name="line.262"></a> |
| <FONT color="green">263</FONT> * @see org.apache.xpath.objects.XNumber<a name="line.263"></a> |
| <FONT color="green">264</FONT> * @see org.apache.xpath.objects.XString<a name="line.264"></a> |
| <FONT color="green">265</FONT> * @see org.apache.xpath.objects.XRTreeFrag<a name="line.265"></a> |
| <FONT color="green">266</FONT> *<a name="line.266"></a> |
| <FONT color="green">267</FONT> * @throws TransformerException<a name="line.267"></a> |
| <FONT color="green">268</FONT> */<a name="line.268"></a> |
| <FONT color="green">269</FONT> public XObject eval(Node contextNode, String str, Node namespaceNode)<a name="line.269"></a> |
| <FONT color="green">270</FONT> throws TransformerException<a name="line.270"></a> |
| <FONT color="green">271</FONT> {<a name="line.271"></a> |
| <FONT color="green">272</FONT> <a name="line.272"></a> |
| <FONT color="green">273</FONT> // Since we don't have a XML Parser involved here, install some default support<a name="line.273"></a> |
| <FONT color="green">274</FONT> // for things like namespaces, etc.<a name="line.274"></a> |
| <FONT color="green">275</FONT> // (Changed from: XPathContext xpathSupport = new XPathContext();<a name="line.275"></a> |
| <FONT color="green">276</FONT> // because XPathContext is weak in a number of areas... perhaps<a name="line.276"></a> |
| <FONT color="green">277</FONT> // XPathContext should be done away with.)<a name="line.277"></a> |
| <FONT color="green">278</FONT> <a name="line.278"></a> |
| <FONT color="green">279</FONT> // Create an object to resolve namespace prefixes.<a name="line.279"></a> |
| <FONT color="green">280</FONT> // XPath namespaces are resolved from the input context node's document element<a name="line.280"></a> |
| <FONT color="green">281</FONT> // if it is a root node, or else the current context node (for lack of a better<a name="line.281"></a> |
| <FONT color="green">282</FONT> // resolution space, given the simplicity of this sample code).<a name="line.282"></a> |
| <FONT color="green">283</FONT> PrefixResolverDefault prefixResolver = new PrefixResolverDefault(<a name="line.283"></a> |
| <FONT color="green">284</FONT> (namespaceNode.getNodeType() == Node.DOCUMENT_NODE)<a name="line.284"></a> |
| <FONT color="green">285</FONT> ? ((Document) namespaceNode).getDocumentElement() : namespaceNode);<a name="line.285"></a> |
| <FONT color="green">286</FONT> <a name="line.286"></a> |
| <FONT color="green">287</FONT> // Create the XPath object.<a name="line.287"></a> |
| <FONT color="green">288</FONT> XPath xpath = new XPath(str, null, prefixResolver, XPath.SELECT, null);<a name="line.288"></a> |
| <FONT color="green">289</FONT> <a name="line.289"></a> |
| <FONT color="green">290</FONT> // Execute the XPath, and have it return the result<a name="line.290"></a> |
| <FONT color="green">291</FONT> // return xpath.execute(xpathSupport, contextNode, prefixResolver);<a name="line.291"></a> |
| <FONT color="green">292</FONT> int ctxtNode = xpathSupport.getDTMHandleFromNode(contextNode);<a name="line.292"></a> |
| <FONT color="green">293</FONT> <a name="line.293"></a> |
| <FONT color="green">294</FONT> return xpath.execute(xpathSupport, ctxtNode, prefixResolver);<a name="line.294"></a> |
| <FONT color="green">295</FONT> }<a name="line.295"></a> |
| <FONT color="green">296</FONT> <a name="line.296"></a> |
| <FONT color="green">297</FONT> /**<a name="line.297"></a> |
| <FONT color="green">298</FONT> * Evaluate XPath string to an XObject.<a name="line.298"></a> |
| <FONT color="green">299</FONT> * XPath namespace prefixes are resolved from the namespaceNode.<a name="line.299"></a> |
| <FONT color="green">300</FONT> * The implementation of this is a little slow, since it creates<a name="line.300"></a> |
| <FONT color="green">301</FONT> * a number of objects each time it is called. This could be optimized<a name="line.301"></a> |
| <FONT color="green">302</FONT> * to keep the same objects around, but then thread-safety issues would arise.<a name="line.302"></a> |
| <FONT color="green">303</FONT> *<a name="line.303"></a> |
| <FONT color="green">304</FONT> * @param contextNode The node to start searching from.<a name="line.304"></a> |
| <FONT color="green">305</FONT> * @param str A valid XPath string.<a name="line.305"></a> |
| <FONT color="green">306</FONT> * @param prefixResolver Will be called if the parser encounters namespace<a name="line.306"></a> |
| <FONT color="green">307</FONT> * prefixes, to resolve the prefixes to URLs.<a name="line.307"></a> |
| <FONT color="green">308</FONT> * @return An XObject, which can be used to obtain a string, number, nodelist, etc, should never be null.<a name="line.308"></a> |
| <FONT color="green">309</FONT> * @see org.apache.xpath.objects.XObject<a name="line.309"></a> |
| <FONT color="green">310</FONT> * @see org.apache.xpath.objects.XNull<a name="line.310"></a> |
| <FONT color="green">311</FONT> * @see org.apache.xpath.objects.XBoolean<a name="line.311"></a> |
| <FONT color="green">312</FONT> * @see org.apache.xpath.objects.XNumber<a name="line.312"></a> |
| <FONT color="green">313</FONT> * @see org.apache.xpath.objects.XString<a name="line.313"></a> |
| <FONT color="green">314</FONT> * @see org.apache.xpath.objects.XRTreeFrag<a name="line.314"></a> |
| <FONT color="green">315</FONT> *<a name="line.315"></a> |
| <FONT color="green">316</FONT> * @throws TransformerException<a name="line.316"></a> |
| <FONT color="green">317</FONT> */<a name="line.317"></a> |
| <FONT color="green">318</FONT> public XObject eval(<a name="line.318"></a> |
| <FONT color="green">319</FONT> Node contextNode, String str, PrefixResolver prefixResolver)<a name="line.319"></a> |
| <FONT color="green">320</FONT> throws TransformerException<a name="line.320"></a> |
| <FONT color="green">321</FONT> {<a name="line.321"></a> |
| <FONT color="green">322</FONT> <a name="line.322"></a> |
| <FONT color="green">323</FONT> // Since we don't have a XML Parser involved here, install some default support<a name="line.323"></a> |
| <FONT color="green">324</FONT> // for things like namespaces, etc.<a name="line.324"></a> |
| <FONT color="green">325</FONT> // (Changed from: XPathContext xpathSupport = new XPathContext();<a name="line.325"></a> |
| <FONT color="green">326</FONT> // because XPathContext is weak in a number of areas... perhaps<a name="line.326"></a> |
| <FONT color="green">327</FONT> // XPathContext should be done away with.)<a name="line.327"></a> |
| <FONT color="green">328</FONT> // Create the XPath object.<a name="line.328"></a> |
| <FONT color="green">329</FONT> XPath xpath = new XPath(str, null, prefixResolver, XPath.SELECT, null);<a name="line.329"></a> |
| <FONT color="green">330</FONT> <a name="line.330"></a> |
| <FONT color="green">331</FONT> // Create an XPathContext that doesn't support pushing and popping of<a name="line.331"></a> |
| <FONT color="green">332</FONT> // variable resolution scopes. Sufficient for simple XPath 1.0 expressions.<a name="line.332"></a> |
| <FONT color="green">333</FONT> XPathContext xpathSupport = new XPathContext(false);<a name="line.333"></a> |
| <FONT color="green">334</FONT> <a name="line.334"></a> |
| <FONT color="green">335</FONT> // Execute the XPath, and have it return the result<a name="line.335"></a> |
| <FONT color="green">336</FONT> int ctxtNode = xpathSupport.getDTMHandleFromNode(contextNode);<a name="line.336"></a> |
| <FONT color="green">337</FONT> <a name="line.337"></a> |
| <FONT color="green">338</FONT> return xpath.execute(xpathSupport, ctxtNode, prefixResolver);<a name="line.338"></a> |
| <FONT color="green">339</FONT> }<a name="line.339"></a> |
| <FONT color="green">340</FONT> }<a name="line.340"></a> |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| </PRE> |
| </BODY> |
| </HTML> |
