/*
    * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
    *
    * This software is open source.
    * See the bottom of this file for the licence.
    */
   
   package org.dom4j.tree;
   
  import java.io.IOException;
  import java.io.StringWriter;
  import java.io.Writer;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  import org.dom4j.Attribute;
  import org.dom4j.CDATA;
  import org.dom4j.CharacterData;
  import org.dom4j.Comment;
  import org.dom4j.Document;
  import org.dom4j.DocumentFactory;
  import org.dom4j.Element;
  import org.dom4j.Entity;
  import org.dom4j.IllegalAddException;
  import org.dom4j.Namespace;
  import org.dom4j.Node;
  import org.dom4j.ProcessingInstruction;
  import org.dom4j.QName;
  import org.dom4j.Text;
  import org.dom4j.Visitor;
  import org.dom4j.io.OutputFormat;
  import org.dom4j.io.XMLWriter;
  
  import org.xml.sax.Attributes;
  
  /***
   * <p>
   * <code>AbstractElement</code> is an abstract base class for tree
   * implementors to use for implementation inheritence.
   * </p>
   * 
   * @author <a href="mailto:jstrachan@apache.org">James Strachan </a>
   * @version $Revision: 1.80 $
   */
  public abstract class AbstractElement extends AbstractBranch implements
          org.dom4j.Element {
      /*** The <code>DocumentFactory</code> instance used by default */
      private static final DocumentFactory DOCUMENT_FACTORY = DocumentFactory
              .getInstance();
  
      protected static final List EMPTY_LIST = Collections.EMPTY_LIST;
  
      protected static final Iterator EMPTY_ITERATOR = EMPTY_LIST.iterator();
  
      protected static final boolean VERBOSE_TOSTRING = false;
  
      protected static final boolean USE_STRINGVALUE_SEPARATOR = false;
  
      public AbstractElement() {
      }
  
      public short getNodeType() {
          return ELEMENT_NODE;
      }
  
      public boolean isRootElement() {
          Document document = getDocument();
  
          if (document != null) {
              Element root = document.getRootElement();
  
              if (root == this) {
                  return true;
              }
          }
  
          return false;
      }
  
      public void setName(String name) {
          setQName(getDocumentFactory().createQName(name));
      }
  
      public void setNamespace(Namespace namespace) {
          setQName(getDocumentFactory().createQName(getName(), namespace));
      }
  
      /***
       * Returns the XPath expression to match this Elements name which is
       * getQualifiedName() if there is a namespace prefix defined or if no
       * namespace is present then it is getName() or if a namespace is defined
       * with no prefix then the expression is [name()='X'] where X = getName().
       * 
       * @return DOCUMENT ME!
       */
      public String getXPathNameStep() {
         String uri = getNamespaceURI();
 
         if ((uri == null) || (uri.length() == 0)) {
             return getName();
         }
 
         String prefix = getNamespacePrefix();
 
         if ((prefix == null) || (prefix.length() == 0)) {
             return "*[name()='" + getName() + "']";
         }
 
         return getQualifiedName();
     }
 
     public String getPath(Element context) {
         if (this == context) {
             return ".";
         }
 
         Element parent = getParent();
 
         if (parent == null) {
             return "/" + getXPathNameStep();
         } else if (parent == context) {
             return getXPathNameStep();
         }
 
         return parent.getPath(context) + "/" + getXPathNameStep();
     }
 
     public String getUniquePath(Element context) {
         Element parent = getParent();
 
         if (parent == null) {
             return "/" + getXPathNameStep();
         }
 
         StringBuffer buffer = new StringBuffer();
 
         if (parent != context) {
             buffer.append(parent.getUniquePath(context));
 
             buffer.append("/");
         }
 
         buffer.append(getXPathNameStep());
 
         List mySiblings = parent.elements(getQName());
 
         if (mySiblings.size() > 1) {
             int idx = mySiblings.indexOf(this);
 
             if (idx >= 0) {
                 buffer.append("[");
 
                 buffer.append(Integer.toString(++idx));
 
                 buffer.append("]");
             }
         }
 
         return buffer.toString();
     }
 
     public String asXML() {
         try {
             StringWriter out = new StringWriter();
             XMLWriter writer = new XMLWriter(out, new OutputFormat());
 
             writer.write(this);
             writer.flush();
 
             return out.toString();
         } catch (IOException e) {
             throw new RuntimeException("IOException while generating "
                     + "textual representation: " + e.getMessage());
         }
     }
 
     public void write(Writer out) throws IOException {
         XMLWriter writer = new XMLWriter(out, new OutputFormat());
         writer.write(this);
     }
 
     /***
      * <p>
      * <code>accept</code> method is the <code>Visitor Pattern</code>
      * method.
      * </p>
      * 
      * @param visitor
      *            <code>Visitor</code> is the visitor.
      */
     public void accept(Visitor visitor) {
         visitor.visit(this);
 
         // visit attributes
         for (int i = 0, size = attributeCount(); i < size; i++) {
             Attribute attribute = attribute(i);
 
             visitor.visit(attribute);
         }
 
         // visit content
         for (int i = 0, size = nodeCount(); i < size; i++) {
             Node node = node(i);
 
             node.accept(visitor);
         }
     }
 
     public String toString() {
         String uri = getNamespaceURI();
 
         if ((uri != null) && (uri.length() > 0)) {
             if (VERBOSE_TOSTRING) {
                 return super.toString() + " [Element: <" + getQualifiedName()
                         + " uri: " + uri + " attributes: " + attributeList()
                         + " content: " + contentList() + " />]";
             } else {
                 return super.toString() + " [Element: <" + getQualifiedName()
                         + " uri: " + uri + " attributes: " + attributeList()
                         + "/>]";
             }
         } else {
             if (VERBOSE_TOSTRING) {
                 return super.toString() + " [Element: <" + getQualifiedName()
                         + " attributes: " + attributeList() + " content: "
                         + contentList() + " />]";
             } else {
                 return super.toString() + " [Element: <" + getQualifiedName()
                         + " attributes: " + attributeList() + "/>]";
             }
         }
     }
 
     // QName methods
     // -------------------------------------------------------------------------
     public Namespace getNamespace() {
         return getQName().getNamespace();
     }
 
     public String getName() {
         return getQName().getName();
     }
 
     public String getNamespacePrefix() {
         return getQName().getNamespacePrefix();
     }
 
     public String getNamespaceURI() {
         return getQName().getNamespaceURI();
     }
 
     public String getQualifiedName() {
         return getQName().getQualifiedName();
     }
 
     public Object getData() {
         return getText();
     }
 
     public void setData(Object data) {
         // ignore this method
     }
 
     // Node methods
     // -------------------------------------------------------------------------
     public Node node(int index) {
         if (index >= 0) {
             List list = contentList();
 
             if (index >= list.size()) {
                 return null;
             }
 
             Object node = list.get(index);
 
             if (node != null) {
                 if (node instanceof Node) {
                     return (Node) node;
                 } else {
                     return getDocumentFactory().createText(node.toString());
                 }
             }
         }
 
         return null;
     }
 
     public int indexOf(Node node) {
         return contentList().indexOf(node);
     }
 
     public int nodeCount() {
         return contentList().size();
     }
 
     public Iterator nodeIterator() {
         return contentList().iterator();
     }
 
     // Element methods
     // -------------------------------------------------------------------------
     public Element element(String name) {
         List list = contentList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Element) {
                 Element element = (Element) object;
 
                 if (name.equals(element.getName())) {
                     return element;
                 }
             }
         }
 
         return null;
     }
 
     public Element element(QName qName) {
         List list = contentList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Element) {
                 Element element = (Element) object;
 
                 if (qName.equals(element.getQName())) {
                     return element;
                 }
             }
         }
 
         return null;
     }
 
     public Element element(String name, Namespace namespace) {
         return element(getDocumentFactory().createQName(name, namespace));
     }
 
     public List elements() {
         List list = contentList();
 
         BackedList answer = createResultList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Element) {
                 answer.addLocal(object);
             }
         }
 
         return answer;
     }
 
     public List elements(String name) {
         List list = contentList();
 
         BackedList answer = createResultList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Element) {
                 Element element = (Element) object;
 
                 if (name.equals(element.getName())) {
                     answer.addLocal(element);
                 }
             }
         }
 
         return answer;
     }
 
     public List elements(QName qName) {
         List list = contentList();
 
         BackedList answer = createResultList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Element) {
                 Element element = (Element) object;
 
                 if (qName.equals(element.getQName())) {
                     answer.addLocal(element);
                 }
             }
         }
 
         return answer;
     }
 
     public List elements(String name, Namespace namespace) {
         return elements(getDocumentFactory().createQName(name, namespace));
     }
 
     public Iterator elementIterator() {
         List list = elements();
 
         return list.iterator();
     }
 
     public Iterator elementIterator(String name) {
         List list = elements(name);
 
         return list.iterator();
     }
 
     public Iterator elementIterator(QName qName) {
         List list = elements(qName);
 
         return list.iterator();
     }
 
     public Iterator elementIterator(String name, Namespace ns) {
         return elementIterator(getDocumentFactory().createQName(name, ns));
     }
 
     // Attribute methods
     // -------------------------------------------------------------------------
     public List attributes() {
         return new ContentListFacade(this, attributeList());
     }
 
     public Iterator attributeIterator() {
         return attributeList().iterator();
     }
 
     public Attribute attribute(int index) {
         return (Attribute) attributeList().get(index);
     }
 
     public int attributeCount() {
         return attributeList().size();
     }
 
     public Attribute attribute(String name) {
         List list = attributeList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Attribute attribute = (Attribute) list.get(i);
 
             if (name.equals(attribute.getName())) {
                 return attribute;
             }
         }
 
         return null;
     }
 
     public Attribute attribute(QName qName) {
         List list = attributeList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Attribute attribute = (Attribute) list.get(i);
 
             if (qName.equals(attribute.getQName())) {
                 return attribute;
             }
         }
 
         return null;
     }
 
     public Attribute attribute(String name, Namespace namespace) {
         return attribute(getDocumentFactory().createQName(name, namespace));
     }
 
     /***
      * This method provides a more optimal way of setting all the attributes on
      * an Element particularly for use in {@link org.dom4j.io.SAXReader}.
      * 
      * @param attributes
      *            DOCUMENT ME!
      * @param namespaceStack
      *            DOCUMENT ME!
      * @param noNamespaceAttributes
      *            DOCUMENT ME!
      */
     public void setAttributes(Attributes attributes,
             NamespaceStack namespaceStack, boolean noNamespaceAttributes) {
         // now lets add all attribute values
         int size = attributes.getLength();
 
         if (size > 0) {
             DocumentFactory factory = getDocumentFactory();
 
             if (size == 1) {
                 // allow lazy construction of the List of Attributes
                 String name = attributes.getQName(0);
 
                 if (noNamespaceAttributes || !name.startsWith("xmlns")) {
                     String attributeURI = attributes.getURI(0);
 
                     String attributeLocalName = attributes.getLocalName(0);
 
                     String attributeValue = attributes.getValue(0);
 
                     QName attributeQName = namespaceStack.getAttributeQName(
                             attributeURI, attributeLocalName, name);
 
                     add(factory.createAttribute(this, attributeQName,
                             attributeValue));
                 }
             } else {
                 List list = attributeList(size);
 
                 list.clear();
 
                 for (int i = 0; i < size; i++) {
                     // optimised to avoid the call to attribute(QName) to
                     // lookup an attribute for a given QName
                     String attributeName = attributes.getQName(i);
 
                     if (noNamespaceAttributes
                             || !attributeName.startsWith("xmlns")) {
                         String attributeURI = attributes.getURI(i);
 
                         String attributeLocalName = attributes.getLocalName(i);
 
                         String attributeValue = attributes.getValue(i);
 
                         QName attributeQName = namespaceStack
                                 .getAttributeQName(attributeURI,
                                         attributeLocalName, attributeName);
 
                         Attribute attribute = factory.createAttribute(this,
                                 attributeQName, attributeValue);
 
                         list.add(attribute);
 
                         childAdded(attribute);
                     }
                 }
             }
         }
     }
 
     public String attributeValue(String name) {
         Attribute attrib = attribute(name);
 
         if (attrib == null) {
             return null;
         } else {
             return attrib.getValue();
         }
     }
 
     public String attributeValue(QName qName) {
         Attribute attrib = attribute(qName);
 
         if (attrib == null) {
             return null;
         } else {
             return attrib.getValue();
         }
     }
 
     public String attributeValue(String name, String defaultValue) {
         String answer = attributeValue(name);
 
         return (answer != null) ? answer : defaultValue;
     }
 
     public String attributeValue(QName qName, String defaultValue) {
         String answer = attributeValue(qName);
 
         return (answer != null) ? answer : defaultValue;
     }
 
     /***
      * DOCUMENT ME!
      * 
      * @param name
      *            DOCUMENT ME!
      * @param value
      *            DOCUMENT ME!
      * 
      * @deprecated As of version 0.5. Please use {@link
      *             #addAttribute(String,String)} instead. WILL BE REMOVED IN
      *             dom4j-1.6 !!
      */
     public void setAttributeValue(String name, String value) {
         addAttribute(name, value);
     }
 
     /***
      * DOCUMENT ME!
      * 
      * @param qName
      *            DOCUMENT ME!
      * @param value
      *            DOCUMENT ME!
      * 
      * @deprecated As of version 0.5. Please use {@link
      *             #addAttribute(String,String)} instead. WILL BE REMOVED IN
      *             dom4j-1.6 !!
      */
     public void setAttributeValue(QName qName, String value) {
         addAttribute(qName, value);
     }
 
     public void add(Attribute attribute) {
         if (attribute.getParent() != null) {
             String message = "The Attribute already has an existing parent \""
                     + attribute.getParent().getQualifiedName() + "\"";
 
             throw new IllegalAddException(this, attribute, message);
         }
 
         if (attribute.getValue() == null) {
             // try remove a previous attribute with the same
             // name since adding an attribute with a null value
             // is equivalent to removing it.
             Attribute oldAttribute = attribute(attribute.getQName());
 
             if (oldAttribute != null) {
                 remove(oldAttribute);
             }
         } else {
             attributeList().add(attribute);
 
             childAdded(attribute);
         }
     }
 
     public boolean remove(Attribute attribute) {
         List list = attributeList();
 
         boolean answer = list.remove(attribute);
 
         if (answer) {
             childRemoved(attribute);
         } else {
             // we may have a copy of the attribute
             Attribute copy = attribute(attribute.getQName());
 
             if (copy != null) {
                 list.remove(copy);
 
                 answer = true;
             }
         }
 
         return answer;
     }
 
     // Processing instruction API
     // -------------------------------------------------------------------------
     public List processingInstructions() {
         List list = contentList();
 
         BackedList answer = createResultList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof ProcessingInstruction) {
                 answer.addLocal(object);
             }
         }
 
         return answer;
     }
 
     public List processingInstructions(String target) {
         List list = contentList();
 
         BackedList answer = createResultList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof ProcessingInstruction) {
                 ProcessingInstruction pi = (ProcessingInstruction) object;
 
                 if (target.equals(pi.getName())) {
                     answer.addLocal(pi);
                 }
             }
         }
 
         return answer;
     }
 
     public ProcessingInstruction processingInstruction(String target) {
         List list = contentList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof ProcessingInstruction) {
                 ProcessingInstruction pi = (ProcessingInstruction) object;
 
                 if (target.equals(pi.getName())) {
                     return pi;
                 }
             }
         }
 
         return null;
     }
 
     public boolean removeProcessingInstruction(String target) {
         List list = contentList();
 
         for (Iterator iter = list.iterator(); iter.hasNext();) {
             Object object = iter.next();
 
             if (object instanceof ProcessingInstruction) {
                 ProcessingInstruction pi = (ProcessingInstruction) object;
 
                 if (target.equals(pi.getName())) {
                     iter.remove();
 
                     return true;
                 }
             }
         }
 
         return false;
     }
 
     // Content Model methods
     // -------------------------------------------------------------------------
     public Node getXPathResult(int index) {
         Node answer = node(index);
 
         if ((answer != null) && !answer.supportsParent()) {
             return answer.asXPathResult(this);
         }
 
         return answer;
     }
 
     public Element addAttribute(String name, String value) {
         // adding a null value is equivalent to removing the attribute
         Attribute attribute = attribute(name);
 
         if (value != null) {
             if (attribute == null) {
                 add(getDocumentFactory().createAttribute(this, name, value));
             } else if (attribute.isReadOnly()) {
                 remove(attribute);
 
                 add(getDocumentFactory().createAttribute(this, name, value));
             } else {
                 attribute.setValue(value);
             }
         } else if (attribute != null) {
             remove(attribute);
         }
 
         return this;
     }
 
     public Element addAttribute(QName qName, String value) {
         // adding a null value is equivalent to removing the attribute
         Attribute attribute = attribute(qName);
 
         if (value != null) {
             if (attribute == null) {
                 add(getDocumentFactory().createAttribute(this, qName, value));
             } else if (attribute.isReadOnly()) {
                 remove(attribute);
 
                 add(getDocumentFactory().createAttribute(this, qName, value));
             } else {
                 attribute.setValue(value);
             }
         } else if (attribute != null) {
             remove(attribute);
         }
 
         return this;
     }
 
     public Element addCDATA(String cdata) {
         CDATA node = getDocumentFactory().createCDATA(cdata);
 
         addNewNode(node);
 
         return this;
     }
 
     public Element addComment(String comment) {
         Comment node = getDocumentFactory().createComment(comment);
 
         addNewNode(node);
 
         return this;
     }
 
     public Element addElement(String name) {
         DocumentFactory factory = getDocumentFactory();
 
         int index = name.indexOf(":");
 
         String prefix = "";
 
         String localName = name;
 
         Namespace namespace = null;
 
         if (index > 0) {
             prefix = name.substring(0, index);
 
             localName = name.substring(index + 1);
 
             namespace = getNamespaceForPrefix(prefix);
 
             if (namespace == null) {
                 throw new IllegalAddException("No such namespace prefix: "
                         + prefix + " is in scope on: " + this
                         + " so cannot add element: " + name);
             }
         } else {
             namespace = getNamespaceForPrefix("");
         }
 
         Element node;
 
         if (namespace != null) {
             QName qname = factory.createQName(localName, namespace);
 
             node = factory.createElement(qname);
         } else {
             node = factory.createElement(name);
         }
 
         addNewNode(node);
 
         return node;
     }
 
     public Element addEntity(String name, String text) {
         Entity node = getDocumentFactory().createEntity(name, text);
 
         addNewNode(node);
 
         return this;
     }
 
     public Element addNamespace(String prefix, String uri) {
         Namespace node = getDocumentFactory().createNamespace(prefix, uri);
 
         addNewNode(node);
 
         return this;
     }
 
     public Element addProcessingInstruction(String target, String data) {
         ProcessingInstruction node = getDocumentFactory()
                 .createProcessingInstruction(target, data);
 
         addNewNode(node);
 
         return this;
     }
 
     public Element addProcessingInstruction(String target, Map data) {
         ProcessingInstruction node = getDocumentFactory()
                 .createProcessingInstruction(target, data);
 
         addNewNode(node);
 
         return this;
     }
 
     public Element addText(String text) {
         Text node = getDocumentFactory().createText(text);
 
         addNewNode(node);
 
         return this;
     }
 
     // polymorphic node methods
     public void add(Node node) {
         switch (node.getNodeType()) {
             case ELEMENT_NODE:
                 add((Element) node);
 
                 break;
 
             case ATTRIBUTE_NODE:
                 add((Attribute) node);
 
                 break;
 
             case TEXT_NODE:
                 add((Text) node);
 
                 break;
 
             case CDATA_SECTION_NODE:
                 add((CDATA) node);
 
                 break;
 
             case ENTITY_REFERENCE_NODE:
                 add((Entity) node);
 
                 break;
 
             case PROCESSING_INSTRUCTION_NODE:
                 add((ProcessingInstruction) node);
 
                 break;
 
             case COMMENT_NODE:
                 add((Comment) node);
 
                 break;
 
             /*
              * XXXX: to do! case DOCUMENT_TYPE_NODE: add((DocumentType) node);
              * break;
              */
             case NAMESPACE_NODE:
                 add((Namespace) node);
 
                 break;
 
             default:
                 invalidNodeTypeAddException(node);
         }
     }
 
     public boolean remove(Node node) {
         switch (node.getNodeType()) {
             case ELEMENT_NODE:
                 return remove((Element) node);
 
             case ATTRIBUTE_NODE:
                 return remove((Attribute) node);
 
             case TEXT_NODE:
                 return remove((Text) node);
 
             case CDATA_SECTION_NODE:
                 return remove((CDATA) node);
 
             case ENTITY_REFERENCE_NODE:
                 return remove((Entity) node);
 
             case PROCESSING_INSTRUCTION_NODE:
                 return remove((ProcessingInstruction) node);
 
             case COMMENT_NODE:
                 return remove((Comment) node);
 
             /*
              * case DOCUMENT_TYPE_NODE: return remove((DocumentType) node);
              */
             case NAMESPACE_NODE:
                 return remove((Namespace) node);
 
             default:
                 return false;
         }
     }
 
     // typesafe versions using node classes
     public void add(CDATA cdata) {
         addNode(cdata);
     }
 
     public void add(Comment comment) {
         addNode(comment);
     }
 
     public void add(Element element) {
         addNode(element);
     }
 
     public void add(Entity entity) {
         addNode(entity);
     }
 
     public void add(Namespace namespace) {
         addNode(namespace);
     }
 
     public void add(ProcessingInstruction pi) {
         addNode(pi);
     }
 
     public void add(Text text) {
         addNode(text);
     }
 
     public boolean remove(CDATA cdata) {
         return removeNode(cdata);
     }
 
     public boolean remove(Comment comment) {
         return removeNode(comment);
     }
 
     public boolean remove(Element element) {
         return removeNode(element);
     }
 
     public boolean remove(Entity entity) {
         return removeNode(entity);
     }
 
     public boolean remove(Namespace namespace) {
         return removeNode(namespace);
     }
 
     public boolean remove(ProcessingInstruction pi) {
         return removeNode(pi);
     }
 
     public boolean remove(Text text) {
         return removeNode(text);
     }
 
     // Helper methods
     // -------------------------------------------------------------------------
     public boolean hasMixedContent() {
         List content = contentList();
 
         if ((content == null) || content.isEmpty() || (content.size() < 2)) {
             return false;
         }
 
         Class prevClass = null;
 
         for (Iterator iter = content.iterator(); iter.hasNext();) {
             Object object = iter.next();
 
             Class newClass = object.getClass();
 
             if (newClass != prevClass) {
                 if (prevClass != null) {
                     return true;
                 }
 
                 prevClass = newClass;
             }
         }
 
         return false;
     }
 
     public boolean isTextOnly() {
         List content = contentList();
 
         if ((content == null) || content.isEmpty()) {
             return true;
         }
 
         for (Iterator iter = content.iterator(); iter.hasNext();) {
             Object object = iter.next();
 
             if (!(object instanceof CharacterData)
                     && !(object instanceof String)) {
                 return false;
             }
         }
 
         return true;
     }
 
     public void setText(String text) {
         /* remove all text nodes */
         List allContent = contentList();
 
         if (allContent != null) {
             Iterator it = allContent.iterator();
 
             while (it.hasNext()) {
                 Node node = (Node) it.next();
 
                 switch (node.getNodeType()) {
                     case CDATA_SECTION_NODE:
 
                     // case ENTITY_NODE:
                     case ENTITY_REFERENCE_NODE:
                     case TEXT_NODE:
                         it.remove();
 
                     default:
                         break;
                 }
             }
         }
 
         addText(text);
     }
 
     public String getStringValue() {
         List list = contentList();
 
         int size = list.size();
 
         if (size > 0) {
             if (size == 1) {
                 // optimised to avoid StringBuffer creation
                 return getContentAsStringValue(list.get(0));
             } else {
                 StringBuffer buffer = new StringBuffer();
 
                 for (int i = 0; i < size; i++) {
                     Object node = list.get(i);
 
                     String string = getContentAsStringValue(node);
 
                     if (string.length() > 0) {
                         if (USE_STRINGVALUE_SEPARATOR) {
                             if (buffer.length() > 0) {
                                 buffer.append(' ');
                             }
                         }
 
                         buffer.append(string);
                     }
                 }
 
                 return buffer.toString();
             }
         }
 
         return "";
     }
 
     /***
      * Puts all <code>Text</code> nodes in the full depth of the sub-tree
      * underneath this <code>Node</code>, including attribute nodes, into a
      * "normal" form where only structure (e.g., elements, comments, processing
      * instructions, CDATA sections, and entity references) separates
      * <code>Text</code> nodes, i.e., there are neither adjacent
      * <code>Text</code> nodes nor empty <code>Text</code> nodes. This can
      * be used to ensure that the DOM view of a document is the same as if it
      * were saved and re-loaded, and is useful when operations (such as XPointer
      * lookups) that depend on a particular document tree structure are to be
      * used.In cases where the document contains <code>CDATASections</code>,
      * the normalize operation alone may not be sufficient, since XPointers do
      * not differentiate between <code>Text</code> nodes and
      * <code>CDATASection</code> nodes.
      * 
      * @since DOM Level 2
      */
     public void normalize() {
         List content = contentList();
 
         Text previousText = null;
 
         int i = 0;
 
         while (i < content.size()) {
             Node node = (Node) content.get(i);
 
             if (node instanceof Text) {
                 Text text = (Text) node;
 
                 if (previousText != null) {
                     previousText.appendText(text.getText());
 
                     remove(text);
                 } else {
                     String value = text.getText();
 
                     // only remove empty Text nodes, not whitespace nodes
                     // if ( value == null || value.trim().length() <= 0 ) {
                     if ((value == null) || (value.length() <= 0)) {
                         remove(text);
                     } else {
                         previousText = text;
 
                         i++;
                     }
                 }
             } else {
                 if (node instanceof Element) {
                     Element element = (Element) node;
 
                     element.normalize();
                 }
 
                 previousText = null;
 
                 i++;
             }
         }
     }
 
     public String elementText(String name) {
         Element element = element(name);
 
         return (element != null) ? element.getText() : null;
     }
 
     public String elementText(QName qName) {
         Element element = element(qName);
 
         return (element != null) ? element.getText() : null;
     }
 
     public String elementTextTrim(String name) {
         Element element = element(name);
 
         return (element != null) ? element.getTextTrim() : null;
     }
 
     public String elementTextTrim(QName qName) {
         Element element = element(qName);
 
         return (element != null) ? element.getTextTrim() : null;
     }
 
     // add to me content from another element
     // analagous to the addAll(collection) methods in Java 2 collections
     public void appendAttributes(Element element) {
         for (int i = 0, size = element.attributeCount(); i < size; i++) {
             Attribute attribute = element.attribute(i);
 
             if (attribute.supportsParent()) {
                 addAttribute(attribute.getQName(), attribute.getValue());
             } else {
                 add(attribute);
             }
         }
     }
 
     /***
      * <p>
      * This returns a deep clone of this element. The new element is detached
      * from its parent, and getParent() on the clone will return null.
      * </p>
      * 
      * @return the clone of this element
      */
 
     /*
      * public Object clone() { Element clone = createElement(getQName());
      * clone.appendAttributes(this); clone.appendContent(this); return clone; }
      */
     public Element createCopy() {
         Element clone = createElement(getQName());
 
         clone.appendAttributes(this);
 
         clone.appendContent(this);
 
         return clone;
     }
 
     public Element createCopy(String name) {
         Element clone = createElement(name);
 
         clone.appendAttributes(this);
 
         clone.appendContent(this);
 
         return clone;
     }
 
     public Element createCopy(QName qName) {
         Element clone = createElement(qName);
 
         clone.appendAttributes(this);
 
         clone.appendContent(this);
 
         return clone;
     }
 
     public QName getQName(String qualifiedName) {
         String prefix = "";
 
         String localName = qualifiedName;
 
         int index = qualifiedName.indexOf(":");
 
         if (index > 0) {
             prefix = qualifiedName.substring(0, index);
 
             localName = qualifiedName.substring(index + 1);
         }
 
         Namespace namespace = getNamespaceForPrefix(prefix);
 
         if (namespace != null) {
             return getDocumentFactory().createQName(localName, namespace);
         } else {
             return getDocumentFactory().createQName(localName);
         }
     }
 
     public Namespace getNamespaceForPrefix(String prefix) {
         if (prefix == null) {
             prefix = "";
         }
 
         if (prefix.equals(getNamespacePrefix())) {
             return getNamespace();
         } else if (prefix.equals("xml")) {
             return Namespace.XML_NAMESPACE;
         } else {
             List list = contentList();
 
             int size = list.size();
 
             for (int i = 0; i < size; i++) {
                 Object object = list.get(i);
 
                 if (object instanceof Namespace) {
                     Namespace namespace = (Namespace) object;
 
                     if (prefix.equals(namespace.getPrefix())) {
                         return namespace;
                     }
                 }
             }
         }
 
         Element parent = getParent();
 
         if (parent != null) {
             Namespace answer = parent.getNamespaceForPrefix(prefix);
 
             if (answer != null) {
                 return answer;
             }
         }
 
         if ((prefix == null) || (prefix.length() <= 0)) {
             return Namespace.NO_NAMESPACE;
         }
 
         return null;
     }
 
     public Namespace getNamespaceForURI(String uri) {
         if ((uri == null) || (uri.length() <= 0)) {
             return Namespace.NO_NAMESPACE;
         } else if (uri.equals(getNamespaceURI())) {
             return getNamespace();
         } else {
             List list = contentList();
 
             int size = list.size();
 
             for (int i = 0; i < size; i++) {
                 Object object = list.get(i);
 
                 if (object instanceof Namespace) {
                     Namespace namespace = (Namespace) object;
 
                     if (uri.equals(namespace.getURI())) {
                         return namespace;
                     }
                 }
             }
 
             return null;
         }
     }
 
     public List getNamespacesForURI(String uri) {
         BackedList answer = createResultList();
 
         // if (getNamespaceURI().equals(uri)) {
         //
         // answer.addLocal(getNamespace());
         //
         // }
         List list = contentList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if ((object instanceof Namespace)
                     && ((Namespace) object).getURI().equals(uri)) {
                 answer.addLocal(object);
             }
         }
 
         return answer;
     }
 
     public List declaredNamespaces() {
         BackedList answer = createResultList();
 
         // if (getNamespaceURI().length() > 0) {
         //
         // answer.addLocal(getNamespace());
         //
         // }
         //
         List list = contentList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Namespace) {
                 answer.addLocal(object);
             }
         }
 
         return answer;
     }
 
     public List additionalNamespaces() {
         List list = contentList();
 
         int size = list.size();
 
         BackedList answer = createResultList();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Namespace) {
                 Namespace namespace = (Namespace) object;
 
                 if (!namespace.equals(getNamespace())) {
                     answer.addLocal(namespace);
                 }
             }
         }
 
         return answer;
     }
 
     public List additionalNamespaces(String defaultNamespaceURI) {
         List list = contentList();
 
         BackedList answer = createResultList();
 
         int size = list.size();
 
         for (int i = 0; i < size; i++) {
             Object object = list.get(i);
 
             if (object instanceof Namespace) {
                 Namespace namespace = (Namespace) object;
 
                 if (!defaultNamespaceURI.equals(namespace.getURI())) {
                     answer.addLocal(namespace);
                 }
             }
         }
 
         return answer;
     }
 
     // Implementation helper methods
     // -------------------------------------------------------------------------
 
     /***
      * Ensures that the list of attributes has the given size
      * 
      * @param minCapacity
      *            DOCUMENT ME!
      */
     public void ensureAttributesCapacity(int minCapacity) {
         if (minCapacity > 1) {
             List list = attributeList();
 
             if (list instanceof ArrayList) {
                 ArrayList arrayList = (ArrayList) list;
 
                 arrayList.ensureCapacity(minCapacity);
             }
         }
     }
 
     // Implementation methods
     // -------------------------------------------------------------------------
     protected Element createElement(String name) {
         return getDocumentFactory().createElement(name);
     }
 
     protected Element createElement(QName qName) {
         return getDocumentFactory().createElement(qName);
     }
 
     protected void addNode(Node node) {
         if (node.getParent() != null) {
             // XXX: could clone here
             String message = "The Node already has an existing parent of \""
                     + node.getParent().getQualifiedName() + "\"";
 
             throw new IllegalAddException(this, node, message);
         }
 
         addNewNode(node);
     }
 
     protected void addNode(int index, Node node) {
         if (node.getParent() != null) {
             // XXX: could clone here
             String message = "The Node already has an existing parent of \""
                     + node.getParent().getQualifiedName() + "\"";
 
             throw new IllegalAddException(this, node, message);
         }
 
         addNewNode(index, node);
     }
 
     /***
      * Like addNode() but does not require a parent check
      * 
      * @param node
      *            DOCUMENT ME!
      */
     protected void addNewNode(Node node) {
         contentList().add(node);
 
         childAdded(node);
     }
 
     protected void addNewNode(int index, Node node) {
         contentList().add(index, node);
 
         childAdded(node);
     }
 
     protected boolean removeNode(Node node) {
         boolean answer = contentList().remove(node);
 
         if (answer) {
             childRemoved(node);
         }
 
         return answer;
     }
 
     /***
      * Called when a new child node is added to create any parent relationships
      * 
      * @param node
      *            DOCUMENT ME!
      */
     protected void childAdded(Node node) {
         if (node != null) {
             node.setParent(this);
         }
     }
 
     protected void childRemoved(Node node) {
         if (node != null) {
             node.setParent(null);
 
             node.setDocument(null);
         }
     }
 
     /***
      * DOCUMENT ME!
      * 
      * @return the internal List used to store attributes or creates one if one
      *         is not available
      */
     protected abstract List attributeList();
 
     /***
      * DOCUMENT ME!
      * 
      * @param attributeCount
      *            DOCUMENT ME!
      * 
      * @return the internal List used to store attributes or creates one with
      *         the specified size if one is not available
      */
     protected abstract List attributeList(int attributeCount);
 
     protected DocumentFactory getDocumentFactory() {
         QName qName = getQName();
 
         // QName might be null as we might not have been constructed yet
         if (qName != null) {
             DocumentFactory factory = qName.getDocumentFactory();
 
             if (factory != null) {
                 return factory;
             }
         }
 
         return DOCUMENT_FACTORY;
     }
 
     /***
      * A Factory Method pattern which creates a List implementation used to
      * store attributes
      * 
      * @return DOCUMENT ME!
      */
     protected List createAttributeList() {
         return createAttributeList(DEFAULT_CONTENT_LIST_SIZE);
     }
 
     /***
      * A Factory Method pattern which creates a List implementation used to
      * store attributes
      * 
      * @param size
      *            DOCUMENT ME!
      * 
      * @return DOCUMENT ME!
      */
     protected List createAttributeList(int size) {
         return new ArrayList(size);
     }
 
     protected Iterator createSingleIterator(Object result) {
         return new SingleIterator(result);
     }
 }
 
 /*
  * Redistribution and use of this software and associated documentation
  * ("Software"), with or without modification, are permitted provided that the
  * following conditions are met:
  * 
  * 1. Redistributions of source code must retain copyright statements and
  * notices. Redistributions must also contain a copy of this document.
  * 
  * 2. Redistributions in binary form must reproduce the above copyright notice,
  * this list of conditions and the following disclaimer in the documentation
  * and/or other materials provided with the distribution.
  * 
  * 3. The name "DOM4J" must not be used to endorse or promote products derived
  * from this Software without prior written permission of MetaStuff, Ltd. For
  * written permission, please contact dom4j-info@metastuff.com.
  * 
  * 4. Products derived from this Software may not be called "DOM4J" nor may
  * "DOM4J" appear in their names without prior written permission of MetaStuff,
  * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.