ChildXmlAsStringBinding.java :  » Content-Management-System » hippo-cms » nl » hippo » cocoon » forms » binding » Java Open Source

/*
* Copyright 2001-2008 Hippo (www.hippo.nl)
*
* 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 nl.hippo.cocoon.forms.binding;

import java.io.IOException;
import java.io.StringReader;
import java.util.Properties;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;

import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.forms.binding.AbstractCustomBinding;
import org.apache.cocoon.forms.binding.BindingException;
import org.apache.cocoon.forms.formmodel.Widget;
import org.apache.cocoon.xml.XMLUtils;
import org.apache.commons.jxpath.JXPathContext;
import org.apache.commons.jxpath.Pointer;
import org.apache.commons.jxpath.ri.model.beans.NullPropertyPointer;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * Custom binding for form elements containing XML as a string.
 * It is assumed that the XML in the string has one unique root node
 * as top level element.
 * 
 * @author <a href="mailto:j.joachimsthal@hippo.nl">Jasha Joachimsthal</a>
 */
public class ChildXmlAsStringBinding extends AbstractCustomBinding
{

    /**
     * Serializes the node as String on load.
     *
     * @throws BindingException
     * @see org.apache.cocoon.forms.binding.AbstractCustomBinding#doLoad(org.apache.cocoon.forms.formmodel.Widget,
     *      org.apache.commons.jxpath.JXPathContext)
     */
    protected void doLoad(Widget widget, JXPathContext context) throws BindingException
    {
    Pointer pointer = context.getPointer(this.getXpath());
    Node contextNode = (Node) pointer.getNode();
        try
        {
          Properties props = new Properties();
          props.put(OutputKeys.OMIT_XML_DECLARATION,"yes");

            String xmlAsString=new String("");
            if(contextNode != null && contextNode.hasChildNodes()){
                NodeList children = contextNode.getChildNodes();
                for(int i=0;i<children.getLength();i++){
                    xmlAsString = xmlAsString + XMLUtils.serializeNode((Node)children.item(i),props);
                }
            }
            widget.setValue(xmlAsString);
        }
        catch (ProcessingException e)
        {
            throw new BindingException("Unable to serialize node", e);
        }
    }

    /**
     * Parses and imports the XML String on save.
     * 
     * @throws IOException
     * @throws SAXException
     * @see org.apache.cocoon.forms.binding.AbstractCustomBinding#doSave(org.apache.cocoon.forms.formmodel.Widget,
     *      org.apache.commons.jxpath.JXPathContext)
     */
    protected void doSave(Widget widget, JXPathContext context) throws BindingException,
            SAXException, IOException
    {
        DocumentBuilder builder = null;
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        try
        {
            builder = factory.newDocumentBuilder();
        }
        catch (ParserConfigurationException e)
        {
            throw new BindingException("Problem getting a parser", e);
        }
        String content = (String) widget.getValue();
        if(content!=null)
        {
            content = content.replaceAll("\r\n|\n","");
        
          Document dom = builder.parse(new InputSource(new StringReader(content)));
      Pointer pointer = context.getPointer(this.getXpath());
            if(pointer instanceof NullPropertyPointer)
            {
                pointer = context.createPath(this.getXpath());
            }
      Node contextNode = (Node) pointer.getNode();
      Node result = contextNode.getOwnerDocument().importNode(dom.getDocumentElement(), true);
  
          // remove all of the context node's current children
          while (contextNode.hasChildNodes())
          {
              contextNode.removeChild(contextNode.getFirstChild());
          }
          
          // append new children to context node
          Node child = result;
          while (child != null)
          {
              Node clonedChild = child.cloneNode(true);
              contextNode.appendChild(clonedChild); 
              child = child.getNextSibling();
          }
        }
        else{
            Pointer pointer = context.getPointer(this.getXpath());
            if(!(pointer instanceof NullPropertyPointer))
            {
                Node contextNode = (Node) pointer.getNode();
                while (contextNode.hasChildNodes())
                {
                    contextNode.removeChild(contextNode.getFirstChild());
                }
            }
        }
        content = "";

    }

}