- /*
- * 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 1.29 2004/02/23 10:29:34 aruny 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 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:
- * <pre>
- * xmlns:xalan="http://xml.apache.org/xalan"
- * </pre>
- * @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 <code>nodeset</code>
- * 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, <code>nodeset</code> returns a node-set. If the argument
- * is a string, number, or boolean, then <code>nodeset</code> 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 <code>toString()</code>
- * method on the passed argument.
- * Most of the
- * actual work here is done in <code>MethodResolver</code> and
- * <code>XRTreeFrag</code>.
- * @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 <code>ExpressionContext</code> passed in by the
- * extension mechanism. This must be an XPathContext.
- * @param xpathExtr 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 <code>StringTokenizer</code>.
- * If the first argument is an empty string or contains only delimiters, the result
- * will be an empty NodeSet.
- *
- * Contributed to XalanJ1 by <a href="mailto:benoit.cerrina@writeme.com">Benoit Cerrina</a>.
- *
- * @param myContext an <code>ExpressionContext</code> passed in by the
- * extension mechanism. This must be an XPathContext.
- * @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 <code>StringTokenizer</code>.
- * If the first argument is an empty string or contains only delimiters, the result
- * will be an empty NodeSet.
- *
- * Contributed to XalanJ1 by <a href="mailto:benoit.cerrina@writeme.com">Benoit Cerrina</a>.
- *
- * @param myContext an <code>ExpressionContext</code> passed in by the
- * extension mechanism. This must be an XPathContext.
- * @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.
- *
- * <p>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
- * <a href="http://xml.apache.org/commons/">http://xml.apache.org/commons/</a>.</p>
- *
- * <p>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?)</p>
- *
- * @param myContext an <code>ExpressionContext</code> 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 <code>ExpressionContext</code> 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, ObjectFactory.findClassLoader(), 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);
- }
-
- }
- }
- }