| /* |
| * 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. |
| * |
| */ |
| package org.apache.xml.security.utils; |
| |
| |
| |
| import org.apache.xml.dtm.DTMManager; |
| import org.apache.xml.security.transforms.implementations.FuncHere; |
| import org.apache.xml.security.transforms.implementations.FuncHereContext; |
| import org.apache.xml.utils.PrefixResolver; |
| import org.apache.xml.utils.PrefixResolverDefault; |
| import org.apache.xpath.CachedXPathAPI; |
| import org.apache.xpath.Expression; |
| import org.apache.xpath.XPath; |
| import org.apache.xpath.XPathContext; |
| import org.apache.xpath.compiler.FunctionTable; |
| import org.apache.xpath.objects.XObject; |
| import org.w3c.dom.*; |
| import org.w3c.dom.traversal.NodeIterator; |
| |
| import javax.xml.transform.ErrorListener; |
| import javax.xml.transform.SourceLocator; |
| import javax.xml.transform.TransformerException; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Modifier; |
| |
| /** |
| * |
| * @author $Author$ |
| */ |
| public class CachedXPathFuncHereAPI { |
| |
| static org.apache.commons.logging.Log log = |
| org.apache.commons.logging.LogFactory.getLog(CachedXPathFuncHereAPI.class.getName()); |
| /** |
| * XPathContext, and thus DTMManager and DTMs, persists through multiple |
| * calls to this object. |
| */ |
| FuncHereContext _funcHereContext = null; |
| |
| /** Field _dtmManager */ |
| DTMManager _dtmManager = null; |
| |
| XPathContext _context = null; |
| |
| String xpathStr=null; |
| |
| XPath xpath=null; |
| |
| static FunctionTable _funcTable = null; |
| |
| static { |
| fixupFunctionTable(); |
| } |
| |
| /** |
| * Method getFuncHereContext |
| * @return the context for this object |
| * |
| */ |
| public FuncHereContext getFuncHereContext() { |
| return this._funcHereContext; |
| } |
| |
| /** |
| * Constructor CachedXPathFuncHereAPI |
| * |
| */ |
| private CachedXPathFuncHereAPI() {} |
| |
| /** |
| * Constructor CachedXPathFuncHereAPI |
| * |
| * @param existingXPathContext |
| */ |
| public CachedXPathFuncHereAPI(XPathContext existingXPathContext) { |
| this._dtmManager = existingXPathContext.getDTMManager(); |
| this._context=existingXPathContext; |
| } |
| |
| /** |
| * Constructor CachedXPathFuncHereAPI |
| * |
| * @param previouslyUsed |
| */ |
| public CachedXPathFuncHereAPI(CachedXPathAPI previouslyUsed) { |
| this._dtmManager = previouslyUsed.getXPathContext().getDTMManager(); |
| this._context=previouslyUsed.getXPathContext(); |
| } |
| |
| /** |
| * Use an XPath string to select a single node. XPath namespace |
| * prefixes are resolved from the context node, which may not |
| * be what you want (see the next method). |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode A Node containing a valid XPath string. |
| * @return The first node found that matches the XPath, or null. |
| * |
| * @throws TransformerException |
| */ |
| public Node selectSingleNode(Node contextNode, Node xpathnode) |
| throws TransformerException { |
| return selectSingleNode(contextNode, xpathnode, contextNode); |
| } |
| |
| /** |
| * Use an XPath string to select a single node. |
| * XPath namespace prefixes are resolved from the namespaceNode. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces. |
| * @return The first node found that matches the XPath, or null. |
| * |
| * @throws TransformerException |
| */ |
| public Node selectSingleNode( |
| Node contextNode, Node xpathnode, Node namespaceNode) |
| throws TransformerException { |
| |
| // Have the XObject return its result as a NodeSetDTM. |
| NodeIterator nl = selectNodeIterator(contextNode, xpathnode, |
| namespaceNode); |
| |
| // Return the first node, or null |
| return nl.nextNode(); |
| } |
| |
| /** |
| * Use an XPath string to select a nodelist. |
| * XPath namespace prefixes are resolved from the contextNode. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @return A NodeIterator, should never be null. |
| * |
| * @throws TransformerException |
| */ |
| public NodeIterator selectNodeIterator(Node contextNode, Node xpathnode) |
| throws TransformerException { |
| return selectNodeIterator(contextNode, xpathnode, contextNode); |
| } |
| |
| /** |
| * Use an XPath string to select a nodelist. |
| * XPath namespace prefixes are resolved from the namespaceNode. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces. |
| * @return A NodeIterator, should never be null. |
| * |
| * @throws TransformerException |
| * @deprecated |
| */ |
| public NodeIterator selectNodeIterator( |
| Node contextNode, Node xpathnode, Node namespaceNode) |
| throws TransformerException { |
| |
| // Execute the XPath, and have it return the result |
| XObject list = eval(contextNode, xpathnode, getStrFromNode(xpathnode), namespaceNode); |
| |
| // Have the XObject return its result as a NodeSetDTM. |
| return list.nodeset(); |
| } |
| |
| /** |
| * Use an XPath string to select a nodelist. |
| * XPath namespace prefixes are resolved from the contextNode. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @return A NodeIterator, should never be null. |
| * |
| * @throws TransformerException |
| * @deprecated |
| */ |
| public NodeList selectNodeList(Node contextNode, Node xpathnode) |
| throws TransformerException { |
| return selectNodeList(contextNode, xpathnode, getStrFromNode(xpathnode), contextNode); |
| } |
| |
| /** |
| * Use an XPath string to select a nodelist. |
| * XPath namespace prefixes are resolved from the namespaceNode. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @param str |
| * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces. |
| * @return A NodeIterator, should never be null. |
| * |
| * @throws TransformerException |
| */ |
| public NodeList selectNodeList( |
| Node contextNode, Node xpathnode, String str, Node namespaceNode) |
| throws TransformerException { |
| |
| // Execute the XPath, and have it return the result |
| XObject list = eval(contextNode, xpathnode, str, namespaceNode); |
| |
| // Return a NodeList. |
| return list.nodelist(); |
| } |
| |
| /** |
| * Evaluate XPath string to an XObject. Using this method, |
| * XPath namespace prefixes will be resolved from the namespaceNode. |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @return An XObject, which can be used to obtain a string, number, nodelist, etc, should never be null. |
| * @see org.apache.xpath.objects.XObject |
| * @see org.apache.xpath.objects.XNull |
| * @see org.apache.xpath.objects.XBoolean |
| * @see org.apache.xpath.objects.XNumber |
| * @see org.apache.xpath.objects.XString |
| * @see org.apache.xpath.objects.XRTreeFrag |
| * |
| * @throws TransformerException |
| * @deprecated |
| */ |
| public XObject eval(Node contextNode, Node xpathnode) |
| throws TransformerException { |
| return eval(contextNode, xpathnode, getStrFromNode(xpathnode),contextNode); |
| } |
| |
| /** |
| * Evaluate XPath string to an XObject. |
| * XPath namespace prefixes are resolved from the namespaceNode. |
| * The implementation of this is a little slow, since it creates |
| * a number of objects each time it is called. This could be optimized |
| * to keep the same objects around, but then thread-safety issues would arise. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @param str |
| * @param namespaceNode The node from which prefixes in the XPath will be resolved to namespaces. |
| * @return An XObject, which can be used to obtain a string, number, nodelist, etc, should never be null. |
| * @see org.apache.xpath.objects.XObject |
| * @see org.apache.xpath.objects.XNull |
| * @see org.apache.xpath.objects.XBoolean |
| * @see org.apache.xpath.objects.XNumber |
| * @see org.apache.xpath.objects.XString |
| * @see org.apache.xpath.objects.XRTreeFrag |
| * |
| * @throws TransformerException |
| */ |
| public XObject eval(Node contextNode, Node xpathnode, String str, Node namespaceNode) |
| throws TransformerException { |
| // Create the XPath object. |
| //String str = CachedXPathFuncHereAPI.getStrFromNode(xpathnode); |
| |
| // Since we don't have a XML Parser involved here, install some default support |
| // for things like namespaces, etc. |
| // (Changed from: XPathContext xpathSupport = new XPathContext(); |
| // because XPathContext is weak in a number of areas... perhaps |
| // XPathContext should be done away with.) |
| if (this._funcHereContext == null) { |
| this._funcHereContext = new FuncHereContext(xpathnode, |
| this._dtmManager); |
| } |
| |
| // Create an object to resolve namespace prefixes. |
| // XPath namespaces are resolved from the input context node's document element |
| // if it is a root node, or else the current context node (for lack of a better |
| // resolution space, given the simplicity of this sample code). |
| PrefixResolverDefault prefixResolver = |
| new PrefixResolverDefault((namespaceNode.getNodeType() |
| == Node.DOCUMENT_NODE) |
| ? ((Document) namespaceNode) |
| .getDocumentElement() |
| : namespaceNode); |
| |
| if (str!=xpathStr) { |
| if (str.indexOf("here()")>0) { |
| _context.reset(); |
| _dtmManager=_context.getDTMManager(); |
| } |
| xpath = createXPath(str, prefixResolver); |
| xpathStr=str; |
| } |
| |
| // Execute the XPath, and have it return the result |
| // return xpath.execute(xpathSupport, contextNode, prefixResolver); |
| int ctxtNode = this._funcHereContext.getDTMHandleFromNode(contextNode); |
| |
| return xpath.execute(this._funcHereContext, ctxtNode, prefixResolver); |
| } |
| |
| /** |
| * Evaluate XPath string to an XObject. |
| * XPath namespace prefixes are resolved from the namespaceNode. |
| * The implementation of this is a little slow, since it creates |
| * a number of objects each time it is called. This could be optimized |
| * to keep the same objects around, but then thread-safety issues would arise. |
| * |
| * @param contextNode The node to start searching from. |
| * @param xpathnode |
| * @param str |
| * @param prefixResolver Will be called if the parser encounters namespace |
| * prefixes, to resolve the prefixes to URLs. |
| * @return An XObject, which can be used to obtain a string, number, nodelist, etc, should never be null. |
| * @see org.apache.xpath.objects.XObject |
| * @see org.apache.xpath.objects.XNull |
| * @see org.apache.xpath.objects.XBoolean |
| * @see org.apache.xpath.objects.XNumber |
| * @see org.apache.xpath.objects.XString |
| * @see org.apache.xpath.objects.XRTreeFrag |
| * |
| * @throws TransformerException |
| */ |
| public XObject eval( |
| Node contextNode, Node xpathnode, String str, PrefixResolver prefixResolver) |
| throws TransformerException { |
| |
| // Since we don't have a XML Parser involved here, install some default support |
| // for things like namespaces, etc. |
| // (Changed from: XPathContext xpathSupport = new XPathContext(); |
| // because XPathContext is weak in a number of areas... perhaps |
| // XPathContext should be done away with.) |
| // Create the XPath object. |
| //String str = CachedXPathFuncHereAPI.getStrFromNode(xpathnode); |
| if (str!=xpathStr) { |
| if (str.indexOf("here()")>0) { |
| _context.reset(); |
| _dtmManager=_context.getDTMManager(); |
| } |
| try { |
| xpath = createXPath(str, prefixResolver); |
| } catch (TransformerException ex) { |
| //Try to see if it is a problem with the classloader. |
| Throwable th= ex.getCause(); |
| if (th instanceof ClassNotFoundException) { |
| if (th.getMessage().indexOf("FuncHere")>0) { |
| throw new RuntimeException(I18n.translate("endorsed.jdk1.4.0")/*,*/+ex); |
| } |
| } |
| throw ex; |
| } |
| xpathStr=str; |
| } |
| |
| // Execute the XPath, and have it return the result |
| if (this._funcHereContext == null) { |
| this._funcHereContext = new FuncHereContext(xpathnode, |
| this._dtmManager); |
| } |
| |
| int ctxtNode = this._funcHereContext.getDTMHandleFromNode(contextNode); |
| |
| return xpath.execute(this._funcHereContext, ctxtNode, prefixResolver); |
| } |
| |
| private XPath createXPath(String str, PrefixResolver prefixResolver) throws TransformerException { |
| XPath xpath = null; |
| Class[] classes = new Class[]{String.class, SourceLocator.class, PrefixResolver.class, int.class, |
| ErrorListener.class, FunctionTable.class}; |
| Object[] objects = new Object[]{str, null, prefixResolver, new Integer(XPath.SELECT), null, _funcTable}; |
| try { |
| Constructor constructor = XPath.class.getConstructor(classes); |
| xpath = (XPath) constructor.newInstance(objects); |
| } catch (Throwable t) { |
| } |
| if (xpath == null) { |
| xpath = new XPath(str, null, prefixResolver, XPath.SELECT, null); |
| } |
| return xpath; |
| } |
| |
| /** |
| * Method getStrFromNode |
| * |
| * @param xpathnode |
| * @return the string for the node. |
| */ |
| public static String getStrFromNode(Node xpathnode) { |
| |
| if (xpathnode.getNodeType() == Node.TEXT_NODE) { |
| |
| // we iterate over all siblings of the context node because eventually, |
| // the text is "polluted" with pi's or comments |
| StringBuffer sb = new StringBuffer(); |
| |
| for (Node currentSibling = xpathnode.getParentNode().getFirstChild(); |
| currentSibling != null; |
| currentSibling = currentSibling.getNextSibling()) { |
| if (currentSibling.getNodeType() == Node.TEXT_NODE) { |
| sb.append(((Text) currentSibling).getData()); |
| } |
| } |
| |
| return sb.toString(); |
| } else if (xpathnode.getNodeType() == Node.ATTRIBUTE_NODE) { |
| return ((Attr) xpathnode).getNodeValue(); |
| } else if (xpathnode.getNodeType() == Node.PROCESSING_INSTRUCTION_NODE) { |
| return ((ProcessingInstruction) xpathnode).getNodeValue(); |
| } |
| |
| return null; |
| } |
| |
| private static void fixupFunctionTable() { |
| boolean installed = false; |
| log.info("Registering Here function"); |
| /** |
| * Try to register our here() implementation as internal function. |
| */ |
| try { |
| Class []args = {String.class, Expression.class}; |
| Method installFunction = FunctionTable.class.getMethod("installFunction", args); |
| if ((installFunction.getModifiers() & Modifier.STATIC) != 0) { |
| Object []params = {"here", new FuncHere()}; |
| installFunction.invoke(null, params); |
| installed = true; |
| } |
| } catch (Throwable t) { |
| log.debug("Error installing function using the static installFunction method", t); |
| } |
| if(!installed) { |
| try { |
| _funcTable = new FunctionTable(); |
| Class []args = {String.class, Class.class}; |
| Method installFunction = FunctionTable.class.getMethod("installFunction", args); |
| Object []params = {"here", FuncHere.class}; |
| installFunction.invoke(_funcTable, params); |
| installed = true; |
| } catch (Throwable t) { |
| log.debug("Error installing function using the static installFunction method", t); |
| } |
| } |
| if (log.isDebugEnabled()) { |
| if (installed) { |
| log.debug("Registered class " + FuncHere.class.getName() |
| + " for XPath function 'here()' function in internal table"); |
| } else { |
| log.debug("Unable to register class " + FuncHere.class.getName() |
| + " for XPath function 'here()' function in internal table"); |
| } |
| } |
| } |
| } |
