src/main/java/org/apache/xml/security/signature/XMLSignatureInputDebugger.java - santuario-java - Git at Google

 /**
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements. See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership. The ASF licenses this file
  * to you 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.signature;

 import java.io.IOException;
 import java.io.StringWriter;
 import java.io.Writer;
 import java.util.Arrays;
 import java.util.Set;

 import org.apache.xml.security.c14n.helper.AttrCompare;
 import org.apache.xml.security.utils.XMLUtils;
 import org.w3c.dom.Attr;
 import org.w3c.dom.Comment;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.NamedNodeMap;
 import org.w3c.dom.Node;
 import org.w3c.dom.ProcessingInstruction;

 /**
  * Class XMLSignatureInputDebugger
  */
 public class XMLSignatureInputDebugger {

     /** Field _xmlSignatureInput */
     private Set<Node> xpathNodeSet;

     private Set<String> inclusiveNamespaces;

     /** Field writer */
     private Writer writer;

     /** The HTML Prefix* */
     static final String HTMLPrefix =
         "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\n"
         + "<html>\n"
         + "<head>\n"
         + "<title>Caninical XML node set</title>\n"
         + "<style type=\"text/css\">\n"
         + "<!-- \n"
         + ".INCLUDED { \n"
         + "   color: #000000; \n"
         + "   background-color: \n"
         + "   #FFFFFF; \n"
         + "   font-weight: bold; } \n"
         + ".EXCLUDED { \n"
         + "   color: #666666; \n"
         + "   background-color: \n"
         + "   #999999; } \n"
         + ".INCLUDEDINCLUSIVENAMESPACE { \n"
         + "   color: #0000FF; \n"
         + "   background-color: #FFFFFF; \n"
         + "   font-weight: bold; \n"
         + "   font-style: italic; } \n"
         + ".EXCLUDEDINCLUSIVENAMESPACE { \n"
         + "   color: #0000FF; \n"
         + "   background-color: #999999; \n"
         + "   font-style: italic; } \n"
         + "--> \n"
         + "</style> \n"
         + "</head>\n"
         + "<body bgcolor=\"#999999\">\n"
         + "<h1>Explanation of the output</h1>\n"
         + "<p>The following text contains the nodeset of the given Reference before it is canonicalized. There exist four different styles to indicate how a given node is treated.</p>\n"
         + "<ul>\n"
         + "<li class=\"INCLUDED\">A node which is in the node set is labeled using the INCLUDED style.</li>\n"
         + "<li class=\"EXCLUDED\">A node which is <em>NOT</em> in the node set is labeled EXCLUDED style.</li>\n"
         + "<li class=\"INCLUDEDINCLUSIVENAMESPACE\">A namespace which is in the node set AND in the InclusiveNamespaces PrefixList is labeled using the INCLUDEDINCLUSIVENAMESPACE style.</li>\n"
         + "<li class=\"EXCLUDEDINCLUSIVENAMESPACE\">A namespace which is in NOT the node set AND in the InclusiveNamespaces PrefixList is labeled using the INCLUDEDINCLUSIVENAMESPACE style.</li>\n"
         + "</ul>\n" + "<h1>Output</h1>\n" + "<pre>\n";

     /** HTML Suffix * */
     static final String HTMLSuffix = "</pre></body></html>";

     static final String HTMLExcludePrefix = "<span class=\"EXCLUDED\">";

     static final String HTMLIncludePrefix = "<span class=\"INCLUDED\">";

     static final String HTMLIncludeOrExcludeSuffix = "</span>";

     static final String HTMLIncludedInclusiveNamespacePrefix = "<span class=\"INCLUDEDINCLUSIVENAMESPACE\">";

     static final String HTMLExcludedInclusiveNamespacePrefix = "<span class=\"EXCLUDEDINCLUSIVENAMESPACE\">";

     private static final int NODE_BEFORE_DOCUMENT_ELEMENT = -1;

     private static final int NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT = 0;

     private static final int NODE_AFTER_DOCUMENT_ELEMENT = 1;

     static final AttrCompare ATTR_COMPARE = new AttrCompare();

     /**
      * Constructor XMLSignatureInputDebugger
      *
      * @param xmlSignatureInput the signature to pretty print
      */
     public XMLSignatureInputDebugger(XMLSignatureInput xmlSignatureInput) {
         if (!xmlSignatureInput.isNodeSet()) {
             this.xpathNodeSet = null;
         } else {
             this.xpathNodeSet = xmlSignatureInput.getInputNodeSet();
         }
     }

     /**
      * Constructor XMLSignatureInputDebugger
      *
      * @param xmlSignatureInput the signatur to pretty print
      * @param inclusiveNamespace
      */
     public XMLSignatureInputDebugger(
         XMLSignatureInput xmlSignatureInput,
         Set<String> inclusiveNamespace
     ) {
         this(xmlSignatureInput);
         this.inclusiveNamespaces = inclusiveNamespace;
     }

     /**
      * Method getHTMLRepresentation
      *
      * @return The HTML Representation.
      * @throws XMLSignatureException
      */
     public String getHTMLRepresentation() throws XMLSignatureException {
         if (this.xpathNodeSet == null || this.xpathNodeSet.isEmpty()) {
             return HTMLPrefix + "<blink>no node set, sorry</blink>" + HTMLSuffix;
         }

         // get only a single node as anchor to fetch the owner document
         Node n = this.xpathNodeSet.iterator().next();

         Document doc = XMLUtils.getOwnerDocument(n);

         try {
             this.writer = new StringWriter();

             this.canonicalizeXPathNodeSet(doc);
             this.writer.close();

             return this.writer.toString();
         } catch (IOException ex) {
             throw new XMLSignatureException(ex);
         } finally {
             this.xpathNodeSet = null;
             this.writer = null;
         }
     }

     /**
      * Method canonicalizeXPathNodeSet
      *
      * @param currentNode
      * @throws XMLSignatureException
      * @throws IOException
      */
     private void canonicalizeXPathNodeSet(Node currentNode)
         throws XMLSignatureException, IOException {

         int currentNodeType = currentNode.getNodeType();
         switch (currentNodeType) {


         case Node.ENTITY_NODE:
         case Node.NOTATION_NODE:
         case Node.DOCUMENT_FRAGMENT_NODE:
         case Node.ATTRIBUTE_NODE:
             throw new XMLSignatureException("empty", new Object[]{"An incorrect node was provided for c14n: " + currentNodeType});
         case Node.DOCUMENT_NODE:
             this.writer.write(HTMLPrefix);

             for (Node currentChild = currentNode.getFirstChild();
                 currentChild != null; currentChild = currentChild.getNextSibling()) {
                 this.canonicalizeXPathNodeSet(currentChild);
             }

             this.writer.write(HTMLSuffix);
             break;

         case Node.COMMENT_NODE:
             if (this.xpathNodeSet.contains(currentNode)) {
                 this.writer.write(HTMLIncludePrefix);
             } else {
                 this.writer.write(HTMLExcludePrefix);
             }

             int position = getPositionRelativeToDocumentElement(currentNode);

             if (position == NODE_AFTER_DOCUMENT_ELEMENT) {
                 this.writer.write("\n");
             }

             this.outputCommentToWriter((Comment) currentNode);

             if (position == NODE_BEFORE_DOCUMENT_ELEMENT) {
                 this.writer.write("\n");
             }

             this.writer.write(HTMLIncludeOrExcludeSuffix);
             break;

         case Node.PROCESSING_INSTRUCTION_NODE:
             if (this.xpathNodeSet.contains(currentNode)) {
                 this.writer.write(HTMLIncludePrefix);
             } else {
                 this.writer.write(HTMLExcludePrefix);
             }

             position = getPositionRelativeToDocumentElement(currentNode);

             if (position == NODE_AFTER_DOCUMENT_ELEMENT) {
                 this.writer.write("\n");
             }

             this.outputPItoWriter((ProcessingInstruction) currentNode);

             if (position == NODE_BEFORE_DOCUMENT_ELEMENT) {
                 this.writer.write("\n");
             }

             this.writer.write(HTMLIncludeOrExcludeSuffix);
             break;

         case Node.TEXT_NODE:
         case Node.CDATA_SECTION_NODE:
             if (this.xpathNodeSet.contains(currentNode)) {
                 this.writer.write(HTMLIncludePrefix);
             } else {
                 this.writer.write(HTMLExcludePrefix);
             }

             outputTextToWriter(currentNode.getNodeValue());

             for (Node nextSibling = currentNode.getNextSibling();
                 nextSibling != null
                 && (nextSibling.getNodeType() == Node.TEXT_NODE
                     || nextSibling.getNodeType() == Node.CDATA_SECTION_NODE);
                 nextSibling = nextSibling.getNextSibling()) {
                 /*
                  * The XPath data model allows to select only the first of a
                  * sequence of mixed text and CDATA nodes. But we must output
                  * them all, so we must search:
                  *
                  * @see http://nagoya.apache.org/bugzilla/show_bug.cgi?id=6329
                  */
                 this.outputTextToWriter(nextSibling.getNodeValue());
             }

             this.writer.write(HTMLIncludeOrExcludeSuffix);
             break;

         case Node.ELEMENT_NODE:
             Element currentElement = (Element) currentNode;

             if (this.xpathNodeSet.contains(currentNode)) {
                 this.writer.write(HTMLIncludePrefix);
             } else {
                 this.writer.write(HTMLExcludePrefix);
             }

             this.writer.write("&lt;");
             this.writer.write(currentElement.getTagName());

             this.writer.write(HTMLIncludeOrExcludeSuffix);

             // we output all Attrs which are available
             NamedNodeMap attrs = currentElement.getAttributes();
             int attrsLength = attrs.getLength();
             Attr attrs2[] = new Attr[attrsLength];

             for (int i = 0; i < attrsLength; i++) {
                 attrs2[i] = (Attr)attrs.item(i);
             }

             Arrays.sort(attrs2, ATTR_COMPARE);
             Object attrs3[] = attrs2;

             for (int i = 0; i < attrsLength; i++) {
                 Attr a = (Attr) attrs3[i];
                 boolean included = this.xpathNodeSet.contains(a);
                 boolean inclusive = this.inclusiveNamespaces.contains(a.getName());

                 if (included) {
                     if (inclusive) {
                         // included and inclusive
                         this.writer.write(HTMLIncludedInclusiveNamespacePrefix);
                     } else {
                         // included and not inclusive
                         this.writer.write(HTMLIncludePrefix);
                     }
                 } else {
                     if (inclusive) {
                         // excluded and inclusive
                         this.writer.write(HTMLExcludedInclusiveNamespacePrefix);
                     } else {
                         // excluded and not inclusive
                         this.writer.write(HTMLExcludePrefix);
                     }
                 }

                 this.outputAttrToWriter(a.getNodeName(), a.getNodeValue());
                 this.writer.write(HTMLIncludeOrExcludeSuffix);
             }

             if (this.xpathNodeSet.contains(currentNode)) {
                 this.writer.write(HTMLIncludePrefix);
             } else {
                 this.writer.write(HTMLExcludePrefix);
             }

             this.writer.write("&gt;");

             this.writer.write(HTMLIncludeOrExcludeSuffix);

             // traversal
             for (Node currentChild = currentNode.getFirstChild();
                 currentChild != null;
                 currentChild = currentChild.getNextSibling()) {
                 this.canonicalizeXPathNodeSet(currentChild);
             }

             if (this.xpathNodeSet.contains(currentNode)) {
                 this.writer.write(HTMLIncludePrefix);
             } else {
                 this.writer.write(HTMLExcludePrefix);
             }

             this.writer.write("&lt;/");
             this.writer.write(currentElement.getTagName());
             this.writer.write("&gt;");

             this.writer.write(HTMLIncludeOrExcludeSuffix);
             break;

         case Node.DOCUMENT_TYPE_NODE:
         default:
             break;
         }
     }

     /**
      * Checks whether a Comment or ProcessingInstruction is before or after the
      * document element. This is needed for prepending or appending "\n"s.
      *
      * @param currentNode
      *            comment or pi to check
      * @return NODE_BEFORE_DOCUMENT_ELEMENT,
      *         NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT or
      *         NODE_AFTER_DOCUMENT_ELEMENT
      * @see #NODE_BEFORE_DOCUMENT_ELEMENT
      * @see #NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT
      * @see #NODE_AFTER_DOCUMENT_ELEMENT
      */
     private int getPositionRelativeToDocumentElement(Node currentNode) {
         if (currentNode == null) {
             return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
         }

         Document doc = currentNode.getOwnerDocument();

         if (currentNode.getParentNode() != doc) {
             return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
         }

         Element documentElement = doc.getDocumentElement();

         if (documentElement == null) {
             return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
         }

         if (documentElement == currentNode) {
             return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
         }

         for (Node x = currentNode; x != null; x = x.getNextSibling()) {
             if (x == documentElement) {
                 return NODE_BEFORE_DOCUMENT_ELEMENT;
             }
         }

         return NODE_AFTER_DOCUMENT_ELEMENT;
     }

     /**
      * Normalizes an {@link Attr}ibute value
      *
      * The string value of the node is modified by replacing
      * <UL>
      * <LI>all ampersands (&) with <CODE>&amp;amp;</CODE></LI>
      * <LI>all open angle brackets (<) with <CODE>&amp;lt;</CODE></LI>
      * <LI>all quotation mark characters with <CODE>&amp;quot;</CODE></LI>
      * <LI>and the whitespace characters <CODE>#x9</CODE>, #xA, and #xD,
      * with character references. The character references are written in
      * uppercase hexadecimal with no leading zeroes (for example, <CODE>#xD</CODE>
      * is represented by the character reference <CODE>&amp;#xD;</CODE>)</LI>
      * </UL>
      *
      * @param name
      * @param value
      * @throws IOException
      */
     private void outputAttrToWriter(String name, String value) throws IOException {
         this.writer.write(" ");
         this.writer.write(name);
         this.writer.write("=\"");

         int length = value.length();

         for (int i = 0; i < length; i++) {
             char c = value.charAt(i);

             switch (c) {

             case '&':
                 this.writer.write("&amp;amp;");
                 break;

             case '<':
                 this.writer.write("&amp;lt;");
                 break;

             case '"':
                 this.writer.write("&amp;quot;");
                 break;

             case 0x09: // '\t'
                 this.writer.write("&amp;#x9;");
                 break;

             case 0x0A: // '\n'
                 this.writer.write("&amp;#xA;");
                 break;

             case 0x0D: // '\r'
                 this.writer.write("&amp;#xD;");
                 break;

             default:
                 this.writer.write(c);
                 break;
             }
         }

         this.writer.write("\"");
     }

     /**
      * Normalizes a {@link org.w3c.dom.Comment} value
      *
      * @param currentPI
      * @throws IOException
      */
     private void outputPItoWriter(ProcessingInstruction currentPI) throws IOException {

         if (currentPI == null) {
             return;
         }

         this.writer.write("&lt;?");

         String target = currentPI.getTarget();
         int length = target.length();

         for (int i = 0; i < length; i++) {
             char c = target.charAt(i);

             switch (c) {

             case 0x0D:
                 this.writer.write("&amp;#xD;");
                 break;

             case ' ':
                 this.writer.write("&middot;");
                 break;

             case '\n':
                 this.writer.write("&para;\n");
                 break;

             default:
                 this.writer.write(c);
                 break;
             }
         }

         String data = currentPI.getData();

         length = data.length();

         if (length > 0) {
             this.writer.write(" ");

             for (int i = 0; i < length; i++) {
                 char c = data.charAt(i);

                 switch (c) {

                 case 0x0D:
                     this.writer.write("&amp;#xD;");
                     break;

                 default:
                     this.writer.write(c);
                     break;
                 }
             }
         }

         this.writer.write("?&gt;");
     }

     /**
      * Method outputCommentToWriter
      *
      * @param currentComment
      * @throws IOException
      */
     private void outputCommentToWriter(Comment currentComment) throws IOException {

         if (currentComment == null) {
             return;
         }

         this.writer.write("&lt;!--");

         String data = currentComment.getData();
         int length = data.length();

         for (int i = 0; i < length; i++) {
             char c = data.charAt(i);

             switch (c) {

             case 0x0D:
                 this.writer.write("&amp;#xD;");
                 break;

             case ' ':
                 this.writer.write("&middot;");
                 break;

             case '\n':
                 this.writer.write("&para;\n");
                 break;

             default:
                 this.writer.write(c);
                 break;
             }
         }

         this.writer.write("--&gt;");
     }

     /**
      * Method outputTextToWriter
      *
      * @param text
      * @throws IOException
      */
     private void outputTextToWriter(String text) throws IOException {
         if (text == null) {
             return;
         }

         int length = text.length();

         for (int i = 0; i < length; i++) {
             char c = text.charAt(i);

             switch (c) {

             case '&':
                 this.writer.write("&amp;amp;");
                 break;

             case '<':
                 this.writer.write("&amp;lt;");
                 break;

             case '>':
                 this.writer.write("&amp;gt;");
                 break;

             case 0xD:
                 this.writer.write("&amp;#xD;");
                 break;

             case ' ':
                 this.writer.write("&middot;");
                 break;

             case '\n':
                 this.writer.write("&para;\n");
                 break;

             default:
                 this.writer.write(c);
                 break;
             }
         }
     }
 }
	/**
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you 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.signature;

	import java.io.IOException;
	import java.io.StringWriter;
	import java.io.Writer;
	import java.util.Arrays;
	import java.util.Set;

	import org.apache.xml.security.c14n.helper.AttrCompare;
	import org.apache.xml.security.utils.XMLUtils;
	import org.w3c.dom.Attr;
	import org.w3c.dom.Comment;
	import org.w3c.dom.Document;
	import org.w3c.dom.Element;
	import org.w3c.dom.NamedNodeMap;
	import org.w3c.dom.Node;
	import org.w3c.dom.ProcessingInstruction;

	/**
	* Class XMLSignatureInputDebugger
	*/
	public class XMLSignatureInputDebugger {

	/** Field _xmlSignatureInput */
	private Set<Node> xpathNodeSet;

	private Set<String> inclusiveNamespaces;

	/** Field writer */
	private Writer writer;

	/** The HTML Prefix* */
	static final String HTMLPrefix =
	"<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\n"
	+ "<html>\n"
	+ "<head>\n"
	+ "<title>Caninical XML node set</title>\n"
	+ "<style type=\"text/css\">\n"
	+ "<!-- \n"
	+ ".INCLUDED { \n"
	+ " color: #000000; \n"
	+ " background-color: \n"
	+ " #FFFFFF; \n"
	+ " font-weight: bold; } \n"
	+ ".EXCLUDED { \n"
	+ " color: #666666; \n"
	+ " background-color: \n"
	+ " #999999; } \n"
	+ ".INCLUDEDINCLUSIVENAMESPACE { \n"
	+ " color: #0000FF; \n"
	+ " background-color: #FFFFFF; \n"
	+ " font-weight: bold; \n"
	+ " font-style: italic; } \n"
	+ ".EXCLUDEDINCLUSIVENAMESPACE { \n"
	+ " color: #0000FF; \n"
	+ " background-color: #999999; \n"
	+ " font-style: italic; } \n"
	+ "--> \n"
	+ "</style> \n"
	+ "</head>\n"
	+ "<body bgcolor=\"#999999\">\n"
	+ "<h1>Explanation of the output</h1>\n"
	+ "<p>The following text contains the nodeset of the given Reference before it is canonicalized. There exist four different styles to indicate how a given node is treated.</p>\n"
	+ "<ul>\n"
	+ "<li class=\"INCLUDED\">A node which is in the node set is labeled using the INCLUDED style.</li>\n"
	+ "<li class=\"EXCLUDED\">A node which is <em>NOT</em> in the node set is labeled EXCLUDED style.</li>\n"
	+ "<li class=\"INCLUDEDINCLUSIVENAMESPACE\">A namespace which is in the node set AND in the InclusiveNamespaces PrefixList is labeled using the INCLUDEDINCLUSIVENAMESPACE style.</li>\n"
	+ "<li class=\"EXCLUDEDINCLUSIVENAMESPACE\">A namespace which is in NOT the node set AND in the InclusiveNamespaces PrefixList is labeled using the INCLUDEDINCLUSIVENAMESPACE style.</li>\n"
	+ "</ul>\n" + "<h1>Output</h1>\n" + "<pre>\n";

	/** HTML Suffix * */
	static final String HTMLSuffix = "</pre></body></html>";

	static final String HTMLExcludePrefix = "<span class=\"EXCLUDED\">";

	static final String HTMLIncludePrefix = "<span class=\"INCLUDED\">";

	static final String HTMLIncludeOrExcludeSuffix = "</span>";

	static final String HTMLIncludedInclusiveNamespacePrefix = "<span class=\"INCLUDEDINCLUSIVENAMESPACE\">";

	static final String HTMLExcludedInclusiveNamespacePrefix = "<span class=\"EXCLUDEDINCLUSIVENAMESPACE\">";

	private static final int NODE_BEFORE_DOCUMENT_ELEMENT = -1;

	private static final int NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT = 0;

	private static final int NODE_AFTER_DOCUMENT_ELEMENT = 1;

	static final AttrCompare ATTR_COMPARE = new AttrCompare();

	/**
	* Constructor XMLSignatureInputDebugger
	*
	* @param xmlSignatureInput the signature to pretty print
	*/
	public XMLSignatureInputDebugger(XMLSignatureInput xmlSignatureInput) {
	if (!xmlSignatureInput.isNodeSet()) {
	this.xpathNodeSet = null;
	} else {
	this.xpathNodeSet = xmlSignatureInput.getInputNodeSet();
	}
	}

	/**
	* Constructor XMLSignatureInputDebugger
	*
	* @param xmlSignatureInput the signatur to pretty print
	* @param inclusiveNamespace
	*/
	public XMLSignatureInputDebugger(
	XMLSignatureInput xmlSignatureInput,
	Set<String> inclusiveNamespace
	) {
	this(xmlSignatureInput);
	this.inclusiveNamespaces = inclusiveNamespace;
	}

	/**
	* Method getHTMLRepresentation
	*
	* @return The HTML Representation.
	* @throws XMLSignatureException
	*/
	public String getHTMLRepresentation() throws XMLSignatureException {
	if (this.xpathNodeSet == null \|\| this.xpathNodeSet.isEmpty()) {
	return HTMLPrefix + "<blink>no node set, sorry</blink>" + HTMLSuffix;
	}

	// get only a single node as anchor to fetch the owner document
	Node n = this.xpathNodeSet.iterator().next();

	Document doc = XMLUtils.getOwnerDocument(n);

	try {
	this.writer = new StringWriter();

	this.canonicalizeXPathNodeSet(doc);
	this.writer.close();

	return this.writer.toString();
	} catch (IOException ex) {
	throw new XMLSignatureException(ex);
	} finally {
	this.xpathNodeSet = null;
	this.writer = null;
	}
	}

	/**
	* Method canonicalizeXPathNodeSet
	*
	* @param currentNode
	* @throws XMLSignatureException
	* @throws IOException
	*/
	private void canonicalizeXPathNodeSet(Node currentNode)
	throws XMLSignatureException, IOException {

	int currentNodeType = currentNode.getNodeType();
	switch (currentNodeType) {


	case Node.ENTITY_NODE:
	case Node.NOTATION_NODE:
	case Node.DOCUMENT_FRAGMENT_NODE:
	case Node.ATTRIBUTE_NODE:
	throw new XMLSignatureException("empty", new Object[]{"An incorrect node was provided for c14n: " + currentNodeType});
	case Node.DOCUMENT_NODE:
	this.writer.write(HTMLPrefix);

	for (Node currentChild = currentNode.getFirstChild();
	currentChild != null; currentChild = currentChild.getNextSibling()) {
	this.canonicalizeXPathNodeSet(currentChild);
	}

	this.writer.write(HTMLSuffix);
	break;

	case Node.COMMENT_NODE:
	if (this.xpathNodeSet.contains(currentNode)) {
	this.writer.write(HTMLIncludePrefix);
	} else {
	this.writer.write(HTMLExcludePrefix);
	}

	int position = getPositionRelativeToDocumentElement(currentNode);

	if (position == NODE_AFTER_DOCUMENT_ELEMENT) {
	this.writer.write("\n");
	}

	this.outputCommentToWriter((Comment) currentNode);

	if (position == NODE_BEFORE_DOCUMENT_ELEMENT) {
	this.writer.write("\n");
	}

	this.writer.write(HTMLIncludeOrExcludeSuffix);
	break;

	case Node.PROCESSING_INSTRUCTION_NODE:
	if (this.xpathNodeSet.contains(currentNode)) {
	this.writer.write(HTMLIncludePrefix);
	} else {
	this.writer.write(HTMLExcludePrefix);
	}

	position = getPositionRelativeToDocumentElement(currentNode);

	if (position == NODE_AFTER_DOCUMENT_ELEMENT) {
	this.writer.write("\n");
	}

	this.outputPItoWriter((ProcessingInstruction) currentNode);

	if (position == NODE_BEFORE_DOCUMENT_ELEMENT) {
	this.writer.write("\n");
	}

	this.writer.write(HTMLIncludeOrExcludeSuffix);
	break;

	case Node.TEXT_NODE:
	case Node.CDATA_SECTION_NODE:
	if (this.xpathNodeSet.contains(currentNode)) {
	this.writer.write(HTMLIncludePrefix);
	} else {
	this.writer.write(HTMLExcludePrefix);
	}

	outputTextToWriter(currentNode.getNodeValue());

	for (Node nextSibling = currentNode.getNextSibling();
	nextSibling != null
	&& (nextSibling.getNodeType() == Node.TEXT_NODE
	\|\| nextSibling.getNodeType() == Node.CDATA_SECTION_NODE);
	nextSibling = nextSibling.getNextSibling()) {
	/*
	* The XPath data model allows to select only the first of a
	* sequence of mixed text and CDATA nodes. But we must output
	* them all, so we must search:
	*
	* @see http://nagoya.apache.org/bugzilla/show_bug.cgi?id=6329
	*/
	this.outputTextToWriter(nextSibling.getNodeValue());
	}

	this.writer.write(HTMLIncludeOrExcludeSuffix);
	break;

	case Node.ELEMENT_NODE:
	Element currentElement = (Element) currentNode;

	if (this.xpathNodeSet.contains(currentNode)) {
	this.writer.write(HTMLIncludePrefix);
	} else {
	this.writer.write(HTMLExcludePrefix);
	}

	this.writer.write("<");
	this.writer.write(currentElement.getTagName());

	this.writer.write(HTMLIncludeOrExcludeSuffix);

	// we output all Attrs which are available
	NamedNodeMap attrs = currentElement.getAttributes();
	int attrsLength = attrs.getLength();
	Attr attrs2[] = new Attr[attrsLength];

	for (int i = 0; i < attrsLength; i++) {
	attrs2[i] = (Attr)attrs.item(i);
	}

	Arrays.sort(attrs2, ATTR_COMPARE);
	Object attrs3[] = attrs2;

	for (int i = 0; i < attrsLength; i++) {
	Attr a = (Attr) attrs3[i];
	boolean included = this.xpathNodeSet.contains(a);
	boolean inclusive = this.inclusiveNamespaces.contains(a.getName());

	if (included) {
	if (inclusive) {
	// included and inclusive
	this.writer.write(HTMLIncludedInclusiveNamespacePrefix);
	} else {
	// included and not inclusive
	this.writer.write(HTMLIncludePrefix);
	}
	} else {
	if (inclusive) {
	// excluded and inclusive
	this.writer.write(HTMLExcludedInclusiveNamespacePrefix);
	} else {
	// excluded and not inclusive
	this.writer.write(HTMLExcludePrefix);
	}
	}

	this.outputAttrToWriter(a.getNodeName(), a.getNodeValue());
	this.writer.write(HTMLIncludeOrExcludeSuffix);
	}

	if (this.xpathNodeSet.contains(currentNode)) {
	this.writer.write(HTMLIncludePrefix);
	} else {
	this.writer.write(HTMLExcludePrefix);
	}

	this.writer.write(">");

	this.writer.write(HTMLIncludeOrExcludeSuffix);

	// traversal
	for (Node currentChild = currentNode.getFirstChild();
	currentChild != null;
	currentChild = currentChild.getNextSibling()) {
	this.canonicalizeXPathNodeSet(currentChild);
	}

	if (this.xpathNodeSet.contains(currentNode)) {
	this.writer.write(HTMLIncludePrefix);
	} else {
	this.writer.write(HTMLExcludePrefix);
	}

	this.writer.write("</");
	this.writer.write(currentElement.getTagName());
	this.writer.write(">");

	this.writer.write(HTMLIncludeOrExcludeSuffix);
	break;

	case Node.DOCUMENT_TYPE_NODE:
	default:
	break;
	}
	}

	/**
	* Checks whether a Comment or ProcessingInstruction is before or after the
	* document element. This is needed for prepending or appending "\n"s.
	*
	* @param currentNode
	* comment or pi to check
	* @return NODE_BEFORE_DOCUMENT_ELEMENT,
	* NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT or
	* NODE_AFTER_DOCUMENT_ELEMENT
	* @see #NODE_BEFORE_DOCUMENT_ELEMENT
	* @see #NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT
	* @see #NODE_AFTER_DOCUMENT_ELEMENT
	*/
	private int getPositionRelativeToDocumentElement(Node currentNode) {
	if (currentNode == null) {
	return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
	}

	Document doc = currentNode.getOwnerDocument();

	if (currentNode.getParentNode() != doc) {
	return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
	}

	Element documentElement = doc.getDocumentElement();

	if (documentElement == null) {
	return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
	}

	if (documentElement == currentNode) {
	return NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT;
	}

	for (Node x = currentNode; x != null; x = x.getNextSibling()) {
	if (x == documentElement) {
	return NODE_BEFORE_DOCUMENT_ELEMENT;
	}
	}

	return NODE_AFTER_DOCUMENT_ELEMENT;
	}

	/**
	* Normalizes an {@link Attr}ibute value
	*
	* The string value of the node is modified by replacing
	* <UL>
	* <LI>all ampersands (&) with <CODE>&amp;</CODE></LI>
	* <LI>all open angle brackets (<) with <CODE>&lt;</CODE></LI>
	* <LI>all quotation mark characters with <CODE>&quot;</CODE></LI>
	* <LI>and the whitespace characters <CODE>#x9</CODE>, #xA, and #xD,
	* with character references. The character references are written in
	* uppercase hexadecimal with no leading zeroes (for example, <CODE>#xD</CODE>
	* is represented by the character reference <CODE>&#xD;</CODE>)</LI>
	* </UL>
	*
	* @param name
	* @param value
	* @throws IOException
	*/
	private void outputAttrToWriter(String name, String value) throws IOException {
	this.writer.write(" ");
	this.writer.write(name);
	this.writer.write("=\"");

	int length = value.length();

	for (int i = 0; i < length; i++) {
	char c = value.charAt(i);

	switch (c) {

	case '&':
	this.writer.write("&amp;");
	break;

	case '<':
	this.writer.write("&lt;");
	break;

	case '"':
	this.writer.write("&quot;");
	break;

	case 0x09: // '\t'
	this.writer.write("&#x9;");
	break;

	case 0x0A: // '\n'
	this.writer.write("&#xA;");
	break;

	case 0x0D: // '\r'
	this.writer.write("&#xD;");
	break;

	default:
	this.writer.write(c);
	break;
	}
	}

	this.writer.write("\"");
	}

	/**
	* Normalizes a {@link org.w3c.dom.Comment} value
	*
	* @param currentPI
	* @throws IOException
	*/
	private void outputPItoWriter(ProcessingInstruction currentPI) throws IOException {

	if (currentPI == null) {
	return;
	}

	this.writer.write("<?");

	String target = currentPI.getTarget();
	int length = target.length();

	for (int i = 0; i < length; i++) {
	char c = target.charAt(i);

	switch (c) {

	case 0x0D:
	this.writer.write("&#xD;");
	break;

	case ' ':
	this.writer.write("·");
	break;

	case '\n':
	this.writer.write("¶\n");
	break;

	default:
	this.writer.write(c);
	break;
	}
	}

	String data = currentPI.getData();

	length = data.length();

	if (length > 0) {
	this.writer.write(" ");

	for (int i = 0; i < length; i++) {
	char c = data.charAt(i);

	switch (c) {

	case 0x0D:
	this.writer.write("&#xD;");
	break;

	default:
	this.writer.write(c);
	break;
	}
	}
	}

	this.writer.write("?>");
	}

	/**
	* Method outputCommentToWriter
	*
	* @param currentComment
	* @throws IOException
	*/
	private void outputCommentToWriter(Comment currentComment) throws IOException {

	if (currentComment == null) {
	return;
	}

	this.writer.write("<!--");

	String data = currentComment.getData();
	int length = data.length();

	for (int i = 0; i < length; i++) {
	char c = data.charAt(i);

	switch (c) {

	case 0x0D:
	this.writer.write("&#xD;");
	break;

	case ' ':
	this.writer.write("·");
	break;

	case '\n':
	this.writer.write("¶\n");
	break;

	default:
	this.writer.write(c);
	break;
	}
	}

	this.writer.write("-->");
	}

	/**
	* Method outputTextToWriter
	*
	* @param text
	* @throws IOException
	*/
	private void outputTextToWriter(String text) throws IOException {
	if (text == null) {
	return;
	}

	int length = text.length();

	for (int i = 0; i < length; i++) {
	char c = text.charAt(i);

	switch (c) {

	case '&':
	this.writer.write("&amp;");
	break;

	case '<':
	this.writer.write("&lt;");
	break;

	case '>':
	this.writer.write("&gt;");
	break;

	case 0xD:
	this.writer.write("&#xD;");
	break;

	case ' ':
	this.writer.write("·");
	break;

	case '\n':
	this.writer.write("¶\n");
	break;

	default:
	this.writer.write(c);
	break;
	}
	}
	}
	}