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diff --git a/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/iaik/xml/XSLTTransformationImpl.java b/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/iaik/xml/XSLTTransformationImpl.java
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+++ b/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/iaik/xml/XSLTTransformationImpl.java
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+/*
+ * Copyright 2003 Federal Chancellery Austria
+ * MOA-SPSS has been developed in a cooperation between BRZ, the Federal
+ * Chancellery Austria - ICT staff unit, and Graz University of Technology.
+ *
+ * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
+ * the European Commission - subsequent versions of the EUPL (the "Licence");
+ * You may not use this work except in compliance with the Licence.
+ * You may obtain a copy of the Licence at:
+ * http://www.osor.eu/eupl/
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the Licence is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the Licence for the specific language governing permissions and
+ * limitations under the Licence.
+ *
+ * This product combines work with different licenses. See the "NOTICE" text
+ * file for details on the various modules and licenses.
+ * The "NOTICE" text file is part of the distribution. Any derivative works
+ * that you distribute must include a readable copy of the "NOTICE" text file.
+ */
+
+
+package at.gv.egovernment.moa.spss.server.iaik.xml;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Collections;
+
+import org.w3c.dom.Element;
+import org.w3c.dom.NodeList;
+
+import iaik.ixsil.algorithms.CanonicalizationAlgorithm;
+import iaik.ixsil.algorithms.CanonicalizationAlgorithmImplExclusiveCanonicalXML;
+import iaik.ixsil.exceptions.AlgorithmException;
+import iaik.server.modules.xml.XSLTTransformation;
+
+import at.gv.egovernment.moa.util.NodeListAdapter;
+import at.gv.egovernment.moa.util.StreamUtils;
+import at.gv.egovernment.moa.util.XPathException;
+import at.gv.egovernment.moa.util.XPathUtils;
+
+
+/**
+ * A <code>Transformation</code> containing an XSLT transformation.
+ * 
+ * @author Patrick Peck
+ * @version $Id$
+ */
+public class XSLTTransformationImpl
+  extends TransformationImpl
+  implements XSLTTransformation {
+
+  /** The XSLT stylesheet. */
+  private Element styleSheetElement;
+  /** The hash code of the canonicalized stylesheet. If calculated, this value
+   * should be != 0. */
+  private int hashCode;
+
+  /**
+   * Create a new <code>XSLTTransformationImpl</code> object.
+   * 
+   * @param styleSheetElement The XSLT stylesheet element.
+   */
+  public XSLTTransformationImpl(Element styleSheetElement) {
+    setAlgorithmURI(XSLTTransformation.XSLT);
+    setStyleSheetElement(styleSheetElement);
+  }
+
+  /**
+   * Set the XSLT stylesheet element.
+   * 
+   * @param styleSheetElement The XSLT stylesheet element to set.
+   */
+  protected void setStyleSheetElement(Element styleSheetElement) {
+    this.styleSheetElement = styleSheetElement;
+    this.hashCode = 0;
+  }
+
+  /**
+   * @see iaik.server.modules.xml.XSLTTransformation#getStylesheetElement()
+   */
+  public Element getStylesheetElement() {
+    return styleSheetElement;
+  }
+
+  /**
+   * Compare this <code>XSLTTransformation</code> to another.
+   * 
+   * @param other The object to compare this 
+   * <code>XSLTTransformation</code> to.
+   * @return <code>true</code>, if <code>other</code> is an
+   * <code>XSLTTransformation</code> and if the canonicalized representations of
+   * the stylesheets contained in <code>this</code> and <code>other</code>
+   * match. Otherwise, <code>false</code> is returned.
+   * @see java.lang.Object#equals(Object)
+   */
+  public boolean equals(Object other) {
+    if (other instanceof XSLTTransformation) {
+      XSLTTransformation xslt = (XSLTTransformation) other;
+      
+      return compareElements(
+        getStylesheetElement(),
+        xslt.getStylesheetElement());
+    }
+    return false;
+  }
+
+  /**
+   * @see java.lang.Object#hashCode()
+   */
+  public int hashCode() {
+    if (hashCode == 0) {
+      hashCode = calculateHashCode(getStylesheetElement());
+    }
+    return hashCode;
+  }
+
+  /**
+   * Calculate the hash code for a DOM element by canonicalizing it.
+   * 
+   * @param element The DOM element for which the hash code is to be calculated.
+   * @return int The hash code, or <code>0</code>, if it could not be
+   * calculated.
+   */
+  private static int calculateHashCode(Element element) {
+    try {
+      InputStream is = canonicalize(element);
+      byte[] buf = new byte[256];
+      int hashCode = 1;
+      int length;
+      int i;
+  
+      while ((length = is.read(buf)) > 0) {
+        for (i = 0; i < length; i++) {
+          hashCode += buf[i] * 31 + i;
+        }
+      }
+      is.close();
+      return hashCode;
+    } catch (AlgorithmException e) {
+      return 0;
+    } catch (IOException e) {
+      return 0;
+    }
+  }
+
+  /**
+   * Compare two DOM elements by canonicalizing their contents and comparing the
+   * resulting byte stream.
+   * 
+   * @param elem1 The 1st element to compare.
+   * @param elem2 The 2nd element to compare.
+   * @return boolean <code>true</code>, if the elements are considered equal
+   * after canonicalization. Otherwise <code>false</code> is returned.
+   */
+  private static boolean compareElements(Element elem1, Element elem2) {
+    try {
+      InputStream is1 = canonicalize(elem1);
+      InputStream is2 = canonicalize(elem2);
+      return StreamUtils.compareStreams(is1, is2);
+    } catch (AlgorithmException e) {
+      return false;
+    } catch (IOException e) {
+      return false;
+    }
+  }
+
+  /**
+   * Canonicalize a DOM element.
+   * 
+   * @param element The element to canonicalize.
+   * @return InputStream A stream with the canonicalized data.
+   * @throws AlgorithmException An error occurred canonicalizing the element.
+   */
+  private static InputStream canonicalize(Element element)
+    throws AlgorithmException {
+    CanonicalizationAlgorithm c14n =
+      new CanonicalizationAlgorithmImplExclusiveCanonicalXML();
+    NodeList nodeList;
+  
+    try {
+      nodeList = XPathUtils.selectNodeList(element, XPathUtils.ALL_NODES_XPATH);
+    } catch (XPathException e) {
+      nodeList = new NodeListAdapter(Collections.EMPTY_LIST);
+    }
+    c14n.setInput(nodeList);
+    return c14n.canonicalize();
+  }
+
+}