/* * reserved comment block * DO NOT REMOVE OR ALTER! */ /* * Copyright 1999-2004 The Apache Software Foundation. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * $Id: Extensions.java,v 1.2.4.1 2005/09/10 18:53:32 jeffsuttor Exp $ */ package com.sun.org.apache.xalan.internal.lib; import java.util.Hashtable; import java.util.StringTokenizer; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import com.sun.org.apache.xalan.internal.extensions.ExpressionContext; import com.sun.org.apache.xalan.internal.xslt.EnvironmentCheck; import com.sun.org.apache.xpath.internal.NodeSet; import com.sun.org.apache.xpath.internal.objects.XBoolean; import com.sun.org.apache.xpath.internal.objects.XNumber; import com.sun.org.apache.xpath.internal.objects.XObject; import com.sun.org.apache.xalan.internal.utils.ObjectFactory; import org.w3c.dom.Document; import org.w3c.dom.DocumentFragment; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.w3c.dom.Text; import org.w3c.dom.traversal.NodeIterator; import org.xml.sax.SAXNotSupportedException; /** * This class contains many of the Xalan-supplied extensions. * It is accessed by specifying a namespace URI as follows: *
 *    xmlns:xalan="http://xml.apache.org/xalan"
 * 
* @xsl.usage general */ public class Extensions { /** * Constructor Extensions * */ private Extensions(){} // Make sure class cannot be instantiated /** * This method is an extension that implements as a Xalan extension * the node-set function also found in xt and saxon. * If the argument is a Result Tree Fragment, then nodeset * returns a node-set consisting of a single root node as described in * section 11.1 of the XSLT 1.0 Recommendation. If the argument is a * node-set, nodeset returns a node-set. If the argument * is a string, number, or boolean, then nodeset returns * a node-set consisting of a single root node with a single text node * child that is the result of calling the XPath string() function on the * passed parameter. If the argument is anything else, then a node-set * is returned consisting of a single root node with a single text node * child that is the result of calling the java toString() * method on the passed argument. * Most of the * actual work here is done in MethodResolver and * XRTreeFrag. * @param myProcessor Context passed by the extension processor * @param rtf Argument in the stylesheet to the nodeset extension function * * NEEDSDOC ($objectName$) @return */ public static NodeSet nodeset(ExpressionContext myProcessor, Object rtf) { String textNodeValue; if (rtf instanceof NodeIterator) { return new NodeSet((NodeIterator) rtf); } else { if (rtf instanceof String) { textNodeValue = (String) rtf; } else if (rtf instanceof Boolean) { textNodeValue = new XBoolean(((Boolean) rtf).booleanValue()).str(); } else if (rtf instanceof Double) { textNodeValue = new XNumber(((Double) rtf).doubleValue()).str(); } else { textNodeValue = rtf.toString(); } // This no longer will work right since the DTM. // Document myDoc = myProcessor.getContextNode().getOwnerDocument(); try { DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); DocumentBuilder db = dbf.newDocumentBuilder(); Document myDoc = db.newDocument(); Text textNode = myDoc.createTextNode(textNodeValue); DocumentFragment docFrag = myDoc.createDocumentFragment(); docFrag.appendChild(textNode); return new NodeSet(docFrag); } catch(ParserConfigurationException pce) { throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(pce); } } } /** * Returns the intersection of two node-sets. * * @param nl1 NodeList for first node-set * @param nl2 NodeList for second node-set * @return a NodeList containing the nodes in nl1 that are also in nl2 * * Note: The usage of this extension function in the xalan namespace * is deprecated. Please use the same function in the EXSLT sets extension * (http://exslt.org/sets). */ public static NodeList intersection(NodeList nl1, NodeList nl2) { return ExsltSets.intersection(nl1, nl2); } /** * Returns the difference between two node-sets. * * @param nl1 NodeList for first node-set * @param nl2 NodeList for second node-set * @return a NodeList containing the nodes in nl1 that are not in nl2 * * Note: The usage of this extension function in the xalan namespace * is deprecated. Please use the same function in the EXSLT sets extension * (http://exslt.org/sets). */ public static NodeList difference(NodeList nl1, NodeList nl2) { return ExsltSets.difference(nl1, nl2); } /** * Returns node-set containing distinct string values. * * @param nl NodeList for node-set * @return a NodeList with nodes from nl containing distinct string values. * In other words, if more than one node in nl contains the same string value, * only include the first such node found. * * Note: The usage of this extension function in the xalan namespace * is deprecated. Please use the same function in the EXSLT sets extension * (http://exslt.org/sets). */ public static NodeList distinct(NodeList nl) { return ExsltSets.distinct(nl); } /** * Returns true if both node-sets contain the same set of nodes. * * @param nl1 NodeList for first node-set * @param nl2 NodeList for second node-set * @return true if nl1 and nl2 contain exactly the same set of nodes. */ public static boolean hasSameNodes(NodeList nl1, NodeList nl2) { NodeSet ns1 = new NodeSet(nl1); NodeSet ns2 = new NodeSet(nl2); if (ns1.getLength() != ns2.getLength()) return false; for (int i = 0; i < ns1.getLength(); i++) { Node n = ns1.elementAt(i); if (!ns2.contains(n)) return false; } return true; } /** * Returns the result of evaluating the argument as a string containing * an XPath expression. Used where the XPath expression is not known until * run-time. The expression is evaluated as if the run-time value of the * argument appeared in place of the evaluate function call at compile time. * * @param myContext an ExpressionContext passed in by the * extension mechanism. This must be an XPathContext. * @param xpathExpr The XPath expression to be evaluated. * @return the XObject resulting from evaluating the XPath * * @throws SAXNotSupportedException * * Note: The usage of this extension function in the xalan namespace * is deprecated. Please use the same function in the EXSLT dynamic extension * (http://exslt.org/dynamic). */ public static XObject evaluate(ExpressionContext myContext, String xpathExpr) throws SAXNotSupportedException { return ExsltDynamic.evaluate(myContext, xpathExpr); } /** * Returns a NodeSet containing one text node for each token in the first argument. * Delimiters are specified in the second argument. * Tokens are determined by a call to StringTokenizer. * If the first argument is an empty string or contains only delimiters, the result * will be an empty NodeSet. * * Contributed to XalanJ1 by Benoit Cerrina. * * @param toTokenize The string to be split into text tokens. * @param delims The delimiters to use. * @return a NodeSet as described above. */ public static NodeList tokenize(String toTokenize, String delims) { Document doc = DocumentHolder.m_doc; StringTokenizer lTokenizer = new StringTokenizer(toTokenize, delims); NodeSet resultSet = new NodeSet(); synchronized (doc) { while (lTokenizer.hasMoreTokens()) { resultSet.addNode(doc.createTextNode(lTokenizer.nextToken())); } } return resultSet; } /** * Returns a NodeSet containing one text node for each token in the first argument. * Delimiters are whitespace. That is, the delimiters that are used are tab ( ), * linefeed ( ), return ( ), and space ( ). * Tokens are determined by a call to StringTokenizer. * If the first argument is an empty string or contains only delimiters, the result * will be an empty NodeSet. * * Contributed to XalanJ1 by Benoit Cerrina. * * @param toTokenize The string to be split into text tokens. * @return a NodeSet as described above. */ public static NodeList tokenize(String toTokenize) { return tokenize(toTokenize, " \t\n\r"); } /** * Return a Node of basic debugging information from the * EnvironmentCheck utility about the Java environment. * *

Simply calls the {@link com.sun.org.apache.xalan.internal.xslt.EnvironmentCheck} * utility to grab info about the Java environment and CLASSPATH, * etc., and then returns the resulting Node. Stylesheets can * then maniuplate this data or simply xsl:copy-of the Node. Note * that we first attempt to load the more advanced * org.apache.env.Which utility by reflection; only if that fails * to we still use the internal version. Which is available from * http://xml.apache.org/commons/.

* *

We throw a WrappedRuntimeException in the unlikely case * that reading information from the environment throws us an * exception. (Is this really the best thing to do?)

* * @param myContext an ExpressionContext passed in by the * extension mechanism. This must be an XPathContext. * @return a Node as described above. */ public static Node checkEnvironment(ExpressionContext myContext) { Document factoryDocument; try { DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); DocumentBuilder db = dbf.newDocumentBuilder(); factoryDocument = db.newDocument(); } catch(ParserConfigurationException pce) { throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(pce); } Node resultNode = null; try { // First use reflection to try to load Which, which is a // better version of EnvironmentCheck resultNode = checkEnvironmentUsingWhich(myContext, factoryDocument); if (null != resultNode) return resultNode; // If reflection failed, fallback to our internal EnvironmentCheck EnvironmentCheck envChecker = new EnvironmentCheck(); Hashtable h = envChecker.getEnvironmentHash(); resultNode = factoryDocument.createElement("checkEnvironmentExtension"); envChecker.appendEnvironmentReport(resultNode, factoryDocument, h); envChecker = null; } catch(Exception e) { throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(e); } return resultNode; } /** * Private worker method to attempt to use org.apache.env.Which. * * @param myContext an ExpressionContext passed in by the * extension mechanism. This must be an XPathContext. * @param factoryDocument providing createElement services, etc. * @return a Node with environment info; null if any error */ private static Node checkEnvironmentUsingWhich(ExpressionContext myContext, Document factoryDocument) { final String WHICH_CLASSNAME = "org.apache.env.Which"; final String WHICH_METHODNAME = "which"; final Class WHICH_METHOD_ARGS[] = { java.util.Hashtable.class, java.lang.String.class, java.lang.String.class }; try { // Use reflection to try to find xml-commons utility 'Which' Class clazz = ObjectFactory.findProviderClass(WHICH_CLASSNAME, true); if (null == clazz) return null; // Fully qualify names since this is the only method they're used in java.lang.reflect.Method method = clazz.getMethod(WHICH_METHODNAME, WHICH_METHOD_ARGS); Hashtable report = new Hashtable(); // Call the method with our Hashtable, common options, and ignore return value Object[] methodArgs = { report, "XmlCommons;Xalan;Xerces;Crimson;Ant", "" }; Object returnValue = method.invoke(null, methodArgs); // Create a parent to hold the report and append hash to it Node resultNode = factoryDocument.createElement("checkEnvironmentExtension"); com.sun.org.apache.xml.internal.utils.Hashtree2Node.appendHashToNode(report, "whichReport", resultNode, factoryDocument); return resultNode; } catch (Throwable t) { // Simply return null; no need to report error return null; } } /** * This class is not loaded until first referenced (see Java Language * Specification by Gosling/Joy/Steele, section 12.4.1) * * The static members are created when this class is first referenced, as a * lazy initialization not needing checking against null or any * synchronization. * */ private static class DocumentHolder { // Reuse the Document object to reduce memory usage. private static final Document m_doc; static { try { m_doc = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument(); } catch(ParserConfigurationException pce) { throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(pce); } } } }