src/org/apache/xml/security/transforms/params/XPathFilterCHGPContainer.java

/*
 * 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.transforms.params;



import org.apache.xml.security.exceptions.XMLSecurityException;
import org.apache.xml.security.transforms.TransformParam;
import org.apache.xml.security.transforms.Transforms;
import org.apache.xml.security.utils.ElementProxy;
import org.apache.xml.security.utils.XMLUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;


/**
 * Implements the parameters for a custom Transform which has a better performance
 * thatn the xfilter2.
 *
 * @author $Author$
 */
public class XPathFilterCHGPContainer extends ElementProxy
        implements TransformParam {

   /** Field _ATT_FILTER_VALUE_INTERSECT */
   private static final String _TAG_INCLUDE_BUT_SEARCH = "IncludeButSearch";

   /** Field _ATT_FILTER_VALUE_SUBTRACT */
   private static final String _TAG_EXCLUDE_BUT_SEARCH = "ExcludeButSearch";

   /** Field _ATT_FILTER_VALUE_UNION */
   private static final String _TAG_EXCLUDE = "Exclude";

   /** Field _TAG_XPATHCHGP */
   public static final String _TAG_XPATHCHGP = "XPathAlternative";

   /** Field _ATT_INCLUDESLASH */
   public static final String _ATT_INCLUDESLASH = "IncludeSlashPolicy";

   /** Field IncludeSlash           */
   public static final boolean IncludeSlash = true;

   /** Field ExcludeSlash           */
   public static final boolean ExcludeSlash = false;

   /**
    * Constructor XPathFilterCHGPContainer
    *
    */
   private XPathFilterCHGPContainer() {

      // no instantiation
   }

   /**
    * Constructor XPathFilterCHGPContainer
    *
    * @param doc
    * @param includeSlashPolicy
    * @param includeButSearch
    * @param excludeButSearch
    * @param exclude
    */
   private XPathFilterCHGPContainer(Document doc, boolean includeSlashPolicy,
                                    String includeButSearch,
                                    String excludeButSearch, String exclude) {

      super(doc);

      if (includeSlashPolicy) {
         this._constructionElement
            .setAttributeNS(null, XPathFilterCHGPContainer._ATT_INCLUDESLASH, "true");
      } else {
         this._constructionElement
            .setAttributeNS(null, XPathFilterCHGPContainer._ATT_INCLUDESLASH, "false");
      }

      if ((includeButSearch != null)
              && (includeButSearch.trim().length() > 0)) {
         Element includeButSearchElem =
            ElementProxy.createElementForFamily(doc, this.getBaseNamespace(),
                                        XPathFilterCHGPContainer
                                           ._TAG_INCLUDE_BUT_SEARCH);

         includeButSearchElem
            .appendChild(this._doc
               .createTextNode(indentXPathText(includeButSearch)));
         this._constructionElement.appendChild(doc.createTextNode("\n"));
         this._constructionElement.appendChild(includeButSearchElem);
      }

      if ((excludeButSearch != null)
              && (excludeButSearch.trim().length() > 0)) {
         Element excludeButSearchElem =
         ElementProxy.createElementForFamily(doc, this.getBaseNamespace(),
                                        XPathFilterCHGPContainer
                                           ._TAG_EXCLUDE_BUT_SEARCH);

         excludeButSearchElem
            .appendChild(this._doc
               .createTextNode(indentXPathText(excludeButSearch)));
         this._constructionElement.appendChild(doc.createTextNode("\n"));
         this._constructionElement.appendChild(excludeButSearchElem);
      }

      if ((exclude != null) && (exclude.trim().length() > 0)) {
         Element excludeElem = ElementProxy.createElementForFamily(doc,
                                  this.getBaseNamespace(),
                                  XPathFilterCHGPContainer._TAG_EXCLUDE);

         excludeElem
            .appendChild(this._doc.createTextNode(indentXPathText(exclude)));
         this._constructionElement.appendChild(doc.createTextNode("\n"));
         this._constructionElement.appendChild(excludeElem);
      }

      this._constructionElement.appendChild(doc.createTextNode("\n"));
   }

   /**
    * Method indentXPathText
    *
    * @param xp
    * @return the string with enters
    */
   static String indentXPathText(String xp) {

      if ((xp.length() > 2) && (!Character.isWhitespace(xp.charAt(0)))) {
         return "\n" + xp + "\n";
      } 
      return xp;
      
   }

   /**
    * Constructor XPathFilterCHGPContainer
    *
    * @param element
    * @param BaseURI
    * @throws XMLSecurityException
    */
   private XPathFilterCHGPContainer(Element element, String BaseURI)
           throws XMLSecurityException {
      super(element, BaseURI);
   }

   /**
    * Creates a new XPathFilterCHGPContainer; needed for generation.
    *
    * @param doc
    * @param includeSlashPolicy
    * @param includeButSearch
    * @param excludeButSearch
    * @param exclude
    * @return the created object
    */
   public static XPathFilterCHGPContainer getInstance(Document doc,
           boolean includeSlashPolicy, String includeButSearch,
           String excludeButSearch, String exclude) {

      return new XPathFilterCHGPContainer(doc, includeSlashPolicy,
                                          includeButSearch, excludeButSearch,
                                          exclude);
   }

   /**
    * Creates a XPathFilterCHGPContainer from an existing Element; needed for verification.
    *
    * @param element
    * @param BaseURI
    *
    * @throws XMLSecurityException
    * @return the created object.
    */
   public static XPathFilterCHGPContainer getInstance(
           Element element, String BaseURI) throws XMLSecurityException {
      return new XPathFilterCHGPContainer(element, BaseURI);
   }

   /**
    * Method getXStr
    *
    * @param type
    * @return The Xstr
    */
   private String getXStr(String type) {

      if (this.length(this.getBaseNamespace(), type) != 1) {
         return "";
      }

      Element xElem = XMLUtils.selectNode(this._constructionElement.getFirstChild(), this.getBaseNamespace(),
                         type,0);

      return XMLUtils.getFullTextChildrenFromElement(xElem);
   }

   /**
    * Method getIncludeButSearch
    *
    * @return the string
    */
   public String getIncludeButSearch() {
      return this.getXStr(XPathFilterCHGPContainer._TAG_INCLUDE_BUT_SEARCH);
   }

   /**
    * Method getExcludeButSearch
    *
    * @return the string
    */
   public String getExcludeButSearch() {
      return this.getXStr(XPathFilterCHGPContainer._TAG_EXCLUDE_BUT_SEARCH);
   }

   /**
    * Method getExclude
    *
    * @return the string
    */
   public String getExclude() {
      return this.getXStr(XPathFilterCHGPContainer._TAG_EXCLUDE);
   }

   /**
    * Method getIncludeSlashPolicy
    *
    * @return the string
    */
   public boolean getIncludeSlashPolicy() {

      return this._constructionElement
         .getAttributeNS(null, XPathFilterCHGPContainer._ATT_INCLUDESLASH)
         .equals("true");
   }

   /**
    * Returns the first Text node which contains information from the XPath
    * Filter String. We must use this stupid hook to enable the here() function
    * to work.
    *
    * $todo$ I dunno whether this crashes: <XPath> he<!-- comment -->re()/ds:Signature[1]</XPath>
    * @param type
    * @return the first Text node which contains information from the XPath 2 Filter String
    */
   private Node getHereContextNode(String type) {

      if (this.length(this.getBaseNamespace(), type) != 1) {
         return null;
      }

      return XMLUtils.selectNodeText(this._constructionElement.getFirstChild(), this.getBaseNamespace(),
                         type,0);
   }

   /**
    * Method getHereContextNodeIncludeButSearch
    *
    * @return the string
    */
   public Node getHereContextNodeIncludeButSearch() {
      return this
         .getHereContextNode(XPathFilterCHGPContainer._TAG_INCLUDE_BUT_SEARCH);
   }

   /**
    * Method getHereContextNodeExcludeButSearch
    *
    * @return the string
    */
   public Node getHereContextNodeExcludeButSearch() {
      return this
         .getHereContextNode(XPathFilterCHGPContainer._TAG_EXCLUDE_BUT_SEARCH);
   }

   /**
    * Method getHereContextNodeExclude
    *
    * @return the string
    */
   public Node getHereContextNodeExclude() {
      return this.getHereContextNode(XPathFilterCHGPContainer._TAG_EXCLUDE);
   }

   /**
    * Method getBaseLocalName
    *
    * @inheritDoc
    */
   public final String getBaseLocalName() {
      return XPathFilterCHGPContainer._TAG_XPATHCHGP;
   }

   /**
    * Method getBaseNamespace
    *
    * @inheritDoc
    */
   public final String getBaseNamespace() {
      return Transforms.TRANSFORM_XPATHFILTERCHGP;
   }
}