/*
* The Apache Software License, Version 1.1
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* originally based on software copyright (c) 2001, Institute for
* Data Communications Systems, <http://www.nue.et-inf.uni-siegen.de/>.
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package org.apache.xml.security.utils;
import javax.xml.transform.TransformerException;
import org.apache.xml.dtm.DTM;
import org.apache.xml.dtm.DTMManager;
import org.apache.xml.dtm.ref.DTMManagerDefault;
import org.apache.xml.dtm.ref.DTMNodeIterator;
import org.apache.xml.dtm.ref.DTMNodeList;
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.compiler.XPathParser;
import org.apache.xpath.objects.XObject;
import org.apache.xpath.XPath;
import org.apache.xpath.XPathContext;
import org.w3c.dom.*;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.traversal.NodeIterator;
/**
*
* @author $Author: geuerp $
*/
public class CachedXPathFuncHereAPI {
/**
* XPathContext, and thus DTMManager and DTMs, persists through multiple
* calls to this object.
*/
FuncHereContext _funcHereContext = null;
/** Field _dtmManager */
DTMManager _dtmManager = null;
/**
* Method getFuncHereContext
*
* @return
*/
public FuncHereContext getFuncHereContext() {
return this._funcHereContext;
}
/**
* Constructor CachedXPathFuncHereAPI
*
*/
private CachedXPathFuncHereAPI() {}
/**
* Constructor CachedXPathFuncHereAPI
*
* @param existingXPathContext
*/
public CachedXPathFuncHereAPI(XPathContext existingXPathContext) {
this._dtmManager = existingXPathContext.getDTMManager();
}
/**
* Constructor CachedXPathFuncHereAPI
*
* @param previouslyUsed
*/
public CachedXPathFuncHereAPI(CachedXPathAPI previouslyUsed) {
this._dtmManager = previouslyUsed.getXPathContext().getDTMManager();
}
/**
* 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
*/
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, 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
*/
public NodeList selectNodeList(Node contextNode, Node xpathnode)
throws TransformerException {
return selectNodeList(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
*/
public NodeList selectNodeList(
Node contextNode, Node xpathnode, Node namespaceNode)
throws TransformerException {
// Execute the XPath, and have it return the result
XObject list = eval(contextNode, xpathnode, 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
*/
public XObject eval(Node contextNode, Node xpathnode)
throws TransformerException {
return eval(contextNode, 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 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, Node namespaceNode)
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.)
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);
// Create the XPath object.
String str = CachedXPathFuncHereAPI.getStrFromNode(xpathnode);
XPath xpath = new XPath(str, null, prefixResolver, XPath.SELECT, null);
// 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 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, 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);
XPath xpath = new XPath(str, null, prefixResolver, XPath.SELECT, null);
// 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);
}
/**
* Method getStrFromNode
*
* @param xpathnode
* @return
*/
private 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;
}
}