src/whiteboard/org/apache/xerces/tree/AttributeSet.java - xerces2-j - Git at Google

 /*
  * $Id$
  *
  * The Apache Software License, Version 1.1
  *
  *
  * Copyright (c) 2000 The Apache Software Foundation.  All rights
  * reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *
  * 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 end-user documentation included with the redistribution,
  *    if any, must include the following acknowledgment:
  *       "This product includes software developed by the
  *        Apache Software Foundation (http://www.apache.org/)."
  *    Alternately, this acknowledgment may appear in the software itself,
  *    if and wherever such third-party acknowledgments normally appear.
  *
  * 4. The names "Crimson" and "Apache Software Foundation" must
  *    not be used to endorse or promote products derived from this
  *    software without prior written permission. For written
  *    permission, please contact apache@apache.org.
  *
  * 5. Products derived from this software may not be called "Apache",
  *    nor may "Apache" appear in their name, without prior written
  *    permission of the Apache Software Foundation.
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  * ====================================================================
  *
  * This software consists of voluntary contributions made by many
  * individuals on behalf of the Apache Software Foundation and was
  * originally based on software copyright (c) 1999, Sun Microsystems, Inc.,
  * http://www.sun.com.  For more information on the Apache Software
  * Foundation, please see <http://www.apache.org/>.
  */

 package org.apache.xerces.tree;


 import java.io.CharArrayWriter;
 import java.io.Writer;
 import java.io.IOException;
 import java.util.Vector;

 import org.w3c.dom.*;

 import org.xml.sax.AttributeList;
 import org.xml.sax.Attributes;
 //import org.xml.sax.Attr;

 // Should move to use the xerces sax2 Attribute impl
 import org.apache.xerces.tree.AttributeListEx;


 /**
  * Class representing an XML attribute list.
  *
  * <P> This couples slightly with the Sun XML parser, in that it optionally
  * uses an extended SAX 1.0 API to see if an attribute was specified in the
  * document or was instead defaulted by attribute processing.
  *
  * @author David Brownell
  * @version $Revision$
  */
 final
 class AttributeSet implements NamedNodeMap, XmlWritable
 {
     private boolean	readonly;
     private Vector	list;
     private ElementNode	nameScope;

     /* Constructs an attribute list, with associated name scope. */
     // package private
     AttributeSet (ElementNode nameScope)
     {
 	list = new Vector (5);
 	this.nameScope = nameScope;
     }

     /*
      * Constructs a copy of an attribute list, for use in cloning.
      * name scopes are set separately.
      */
     // package private
     AttributeSet (AttributeSet original, boolean deep)
     {
 	int		size = original.getLength ();

 	list = new Vector (size);
 	for (int i = 0; i < size; i++) {
 	    Node	node = original.item (i);

 	    if (!(node instanceof AttributeNode))
 		throw new IllegalArgumentException (((NodeBase)node).
 						getMessage ("A-003"));
 	    node = node.cloneNode (deep);

 	    // temporarily undo binding to element ... it's rebound
 	    // by the caller
 	    ((AttributeNode)node).setNameScope (null);
 	    list.addElement (node);
 	}
     }

     // package private
     AttributeSet (AttributeList source)
     throws DOMException
     {
 	int			len = source.getLength ();
 	AttributeListEx		ex = null;

 	list = new Vector (len);
 	if (source instanceof AttributeListEx)
 	    ex = (AttributeListEx) source;

 	for (int i = 0; i < len; i++) {
 	    list.addElement (new AttributeNode (
 		    source.getName (i),
 		    source.getValue (i),
 		    ex == null	// remember if it was specified
 			? true
 			: ex.isSpecified (i),
 		    ex == null	// remember any default value
 			? null
 			: ex.getDefault (i)
 		    ));
 	}
 	list.trimToSize ();
     }

     /**
      * <b>DOM2:</b> Create DOM NamedNodeMap from SAX2 Attributes object
      */
     AttributeSet(Attributes source) throws DOMException {
 	int			len = source.getLength();
 	AttributeListEx		ex = null;

 	list = new Vector(len);
 	if (source instanceof AttributeListEx) { // XXX fix this
 	    ex = (AttributeListEx) source;
         }

 	for (int i = 0; i < len; i++) {
             // Translate "" of SAX2 to null.  See DOM2 spec under Node
             // namespaceURI
             String uri = source.getURI(i);
             if (uri.equals("")) {
                 uri = null;
             }

             AttributeNode attrNode =
                 new AttributeNode(uri,
                                   source.getQName(i),
                                   source.getValue(i),
                                   ex == null	// remember if it was specified
                                   ? true
                                   : ex.isSpecified(i),
                                   ex == null	// remember any default value
                                   ? null
                                   : ex.getDefault(i));
 	    list.addElement(attrNode);
 	}
 	list.trimToSize();
     }

     // package private
     void trimToSize () { list.trimToSize (); }

     // package private
     public void setReadonly ()
     {
 	readonly = true;
 	for (int i = 0; i < list.size (); i++)
 	    ((AttributeNode)list.elementAt (i)).setReadonly (true);
     }

     public boolean isReadonly () {
     	if (readonly)
 	    return true;
 	for (int i = 0; i < list.size (); i++) {
 	    if (((AttributeNode)list.elementAt (i)).isReadonly ()) {
 	   	return true;
 	    }
 	}
 	return false;
     }

     // package private
     void setNameScope (ElementNode e)
     {
 	if (e != null && nameScope != null)
 	    throw new IllegalStateException (e.getMessage ("A-004"));
 	nameScope = e;

 	// need to bind the attributes to this element
 	int	length = list.size ();

 	for (int i = 0; i < length; i++) {
 	    AttributeNode	node;

 	    node = (AttributeNode) list.elementAt (i);
 	    node.setNameScope (null);
 	    node.setNameScope (e);
 	}
     }

     // package private
     ElementNode getNameScope ()
     {
 	return nameScope;
     }


     // package private
     String getValue (String name)
     {
 	Attr	attr = (Attr) getNamedItem (name);

 	if (attr == null)
 	    return "";
 	else
 	    return attr.getValue ();
     }

     public Node getNamedItem (String name)
     {
 	int	length = list.size ();
 	Node	value;

 	for (int i = 0; i < length; i++) {
 	    value = item (i);
 	    if (value.getNodeName ().equals (name))
 		return value;
 	}
 	return null;
     }

     /**
      * <b>DOM2:</b>
      */
     public Node getNamedItemNS(String namespaceURI, String localName) {
 	for (int i = 0; i < list.size(); i++) {
 	    Node value = item(i);
             String iLocalName = value.getLocalName();
 	    if (iLocalName != null && iLocalName.equals(localName)) {
                 String iNamespaceURI = value.getNamespaceURI();
                 if (iNamespaceURI != null
                     && iNamespaceURI.equals(namespaceURI)) {
                     return value;
                 }
             }
 	}
 	return null;
     }

     public int getLength ()
     {
 	return list.size ();
     }

     public Node item (int index)
     {
 	if (index < 0 || index >= list.size ())
 	    return null;
 	return (Node) list.elementAt (index);
     }

     public Node removeNamedItem (String name)
     throws DOMException
     {
 	int		length = list.size ();
 	Node		value;

 	if (readonly)
 	    throw new DomEx (DomEx.NO_MODIFICATION_ALLOWED_ERR);
 	for (int i = 0; i < length; i++) {
 	    value = item (i);
 	    if (value.getNodeName ().equals (name)) {
 		AttributeNode	att = (AttributeNode) value;

 		if (att.getDefaultValue () != null) {
 		    att = new AttributeNode (att);
 		    att.setOwnerDocument ((XmlDocument)
 			    nameScope.getOwnerDocument ());
 		    list.setElementAt (att, i);
 		} else
 		    list.removeElementAt (i);

 		att.setNameScope (null);
 		return value;
 	    }
 	}
 	throw new DomEx (DomEx.NOT_FOUND_ERR);
     }

     /**
      * <b>DOM2:</b>
      */
     public Node removeNamedItemNS(String namespaceURI, String localName)
         throws DOMException
     {
 	if (readonly) {
 	    throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);
         }

 	for (int i = 0; i < list.size(); i++) {
 	    Node value = item(i);
             String iLocalName = value.getLocalName();
 	    if (iLocalName != null && iLocalName.equals(localName)) {
                 String iNamespaceURI = value.getNamespaceURI();
                 if (iNamespaceURI != null
                     && iNamespaceURI.equals(namespaceURI)) {
                     AttributeNode attr = (AttributeNode) value;
                     if (attr.getDefaultValue() != null) {
                         attr = new AttributeNode(attr);
                         list.setElementAt(attr, i);
                     } else {
                         list.removeElementAt(i);
                     }
                     return value;
                 }
             }
 	}
 	throw new DomEx(DomEx.NOT_FOUND_ERR);
     }

     public Node setNamedItem (Node value)
     throws DOMException
     {
 	AttributeNode	node;

 	if (readonly)
 	    throw new DomEx (DomEx.NO_MODIFICATION_ALLOWED_ERR);
 	if (!(value instanceof AttributeNode)
 		|| value.getOwnerDocument ()
 			!= nameScope.getOwnerDocument ())
 	    throw new DomEx (DomEx.WRONG_DOCUMENT_ERR);
 	node = (AttributeNode)value;
 	if (node.getNameScope () != null)
 	    throw new DomEx (DomEx.INUSE_ATTRIBUTE_ERR);

 	int		length = list.size ();
 	AttributeNode	oldValue;

 	for (int i = 0; i < length; i++) {
 	    oldValue = (AttributeNode) item (i);
 	    if (oldValue.getNodeName ().equals (value.getNodeName ())) {
 	    	if (oldValue.isReadonly ())
 	    	    throw new DomEx (DomEx.NO_MODIFICATION_ALLOWED_ERR);
 		node.setNameScope (nameScope);
 		list.setElementAt (value, i);
 		oldValue.setNameScope (null);
 		return oldValue;
 	    }
 	}
 	node.setNameScope (nameScope);
 	list.addElement (value);
 	return null;
     }

     /**
      * <b>DOM2:</b>
      * XXX spec allows Element nodes also, but this code assumes Attr nodes
      * only
      */
     public Node setNamedItemNS(Node arg) throws DOMException {
 	if (readonly) {
 	    throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);
         }

 	AttributeNode attr = (AttributeNode) arg;
         if (attr.getOwnerElement() != null) {
 	    throw new DomEx(DomEx.INUSE_ATTRIBUTE_ERR);
         }

 	for (int i = 0; i < list.size(); i++) {
 	    AttributeNode oldNode = (AttributeNode) item(i);
             String localName = oldNode.getLocalName();
             String namespaceURI = oldNode.getNamespaceURI();
             if (arg.getLocalName().equals(localName)
                 && arg.getNamespaceURI().equals(namespaceURI)) {
                 // Found a matching node so replace it
                 list.setElementAt(arg, i);
                 return oldNode;
             }
 	}

         // Append instead of replace
 	list.addElement(arg);
 	return null;
     }

     /**
      * Writes out the attribute list.  Attributes known to have been
      * derived from the DTD are not (at this time) written out.  Part
      * of writing standalone XML is first ensuring that all attributes
      * are flagged as being specified in the "printed" form (or else
      * are defaulted only in the internal DTD subset).
      */
     public void writeXml (XmlWriteContext context) throws IOException
     {
 	Writer		out = context.getWriter ();
 	int		length = list.size ();
 	AttributeNode	tmp;

 	for (int i = 0; i < length; i++) {
 	    tmp = (AttributeNode) list.elementAt (i);
 	    if (tmp.getSpecified ()) {
 		out.write (' ');
 		tmp.writeXml (context);
 	    }
 	}
     }

     /**
      * Does nothing; this type of node has no children.
      */
     public void writeChildrenXml (XmlWriteContext context) throws IOException
     {
     }

     public String toString ()
     {
 	try {
 	    CharArrayWriter w = new CharArrayWriter ();
 	    XmlWriteContext x = new XmlWriteContext (w);
 	    writeXml (x);
 	    return w.toString ();

 	} catch (IOException e) {
 	    return super.toString ();
 	}
     }
 }
	/*
	* $Id$
	*
	* The Apache Software License, Version 1.1
	*
	*
	* Copyright (c) 2000 The Apache Software Foundation. All rights
	* reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* 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 end-user documentation included with the redistribution,
	* if any, must include the following acknowledgment:
	* "This product includes software developed by the
	* Apache Software Foundation (http://www.apache.org/)."
	* Alternately, this acknowledgment may appear in the software itself,
	* if and wherever such third-party acknowledgments normally appear.
	*
	* 4. The names "Crimson" and "Apache Software Foundation" must
	* not be used to endorse or promote products derived from this
	* software without prior written permission. For written
	* permission, please contact apache@apache.org.
	*
	* 5. Products derived from this software may not be called "Apache",
	* nor may "Apache" appear in their name, without prior written
	* permission of the Apache Software Foundation.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	* ====================================================================
	*
	* This software consists of voluntary contributions made by many
	* individuals on behalf of the Apache Software Foundation and was
	* originally based on software copyright (c) 1999, Sun Microsystems, Inc.,
	* http://www.sun.com. For more information on the Apache Software
	* Foundation, please see <http://www.apache.org/>.
	*/

	package org.apache.xerces.tree;


	import java.io.CharArrayWriter;
	import java.io.Writer;
	import java.io.IOException;
	import java.util.Vector;

	import org.w3c.dom.*;

	import org.xml.sax.AttributeList;
	import org.xml.sax.Attributes;
	//import org.xml.sax.Attr;

	// Should move to use the xerces sax2 Attribute impl
	import org.apache.xerces.tree.AttributeListEx;


	/**
	* Class representing an XML attribute list.
	*
	* <P> This couples slightly with the Sun XML parser, in that it optionally
	* uses an extended SAX 1.0 API to see if an attribute was specified in the
	* document or was instead defaulted by attribute processing.
	*
	* @author David Brownell
	* @version $Revision$
	*/
	final
	class AttributeSet implements NamedNodeMap, XmlWritable
	{
	private boolean readonly;
	private Vector list;
	private ElementNode nameScope;

	/* Constructs an attribute list, with associated name scope. */
	// package private
	AttributeSet (ElementNode nameScope)
	{
	list = new Vector (5);
	this.nameScope = nameScope;
	}

	/*
	* Constructs a copy of an attribute list, for use in cloning.
	* name scopes are set separately.
	*/
	// package private
	AttributeSet (AttributeSet original, boolean deep)
	{
	int size = original.getLength ();

	list = new Vector (size);
	for (int i = 0; i < size; i++) {
	Node node = original.item (i);

	if (!(node instanceof AttributeNode))
	throw new IllegalArgumentException (((NodeBase)node).
	getMessage ("A-003"));
	node = node.cloneNode (deep);

	// temporarily undo binding to element ... it's rebound
	// by the caller
	((AttributeNode)node).setNameScope (null);
	list.addElement (node);
	}
	}

	// package private
	AttributeSet (AttributeList source)
	throws DOMException
	{
	int len = source.getLength ();
	AttributeListEx ex = null;

	list = new Vector (len);
	if (source instanceof AttributeListEx)
	ex = (AttributeListEx) source;

	for (int i = 0; i < len; i++) {
	list.addElement (new AttributeNode (
	source.getName (i),
	source.getValue (i),
	ex == null // remember if it was specified
	? true
	: ex.isSpecified (i),
	ex == null // remember any default value
	? null
	: ex.getDefault (i)
	));
	}
	list.trimToSize ();
	}

	/**
	* <b>DOM2:</b> Create DOM NamedNodeMap from SAX2 Attributes object
	*/
	AttributeSet(Attributes source) throws DOMException {
	int len = source.getLength();
	AttributeListEx ex = null;

	list = new Vector(len);
	if (source instanceof AttributeListEx) { // XXX fix this
	ex = (AttributeListEx) source;
	}

	for (int i = 0; i < len; i++) {
	// Translate "" of SAX2 to null. See DOM2 spec under Node
	// namespaceURI
	String uri = source.getURI(i);
	if (uri.equals("")) {
	uri = null;
	}

	AttributeNode attrNode =
	new AttributeNode(uri,
	source.getQName(i),
	source.getValue(i),
	ex == null // remember if it was specified
	? true
	: ex.isSpecified(i),
	ex == null // remember any default value
	? null
	: ex.getDefault(i));
	list.addElement(attrNode);
	}
	list.trimToSize();
	}

	// package private
	void trimToSize () { list.trimToSize (); }

	// package private
	public void setReadonly ()
	{
	readonly = true;
	for (int i = 0; i < list.size (); i++)
	((AttributeNode)list.elementAt (i)).setReadonly (true);
	}

	public boolean isReadonly () {
	if (readonly)
	return true;
	for (int i = 0; i < list.size (); i++) {
	if (((AttributeNode)list.elementAt (i)).isReadonly ()) {
	return true;
	}
	}
	return false;
	}

	// package private
	void setNameScope (ElementNode e)
	{
	if (e != null && nameScope != null)
	throw new IllegalStateException (e.getMessage ("A-004"));
	nameScope = e;

	// need to bind the attributes to this element
	int length = list.size ();

	for (int i = 0; i < length; i++) {
	AttributeNode node;

	node = (AttributeNode) list.elementAt (i);
	node.setNameScope (null);
	node.setNameScope (e);
	}
	}

	// package private
	ElementNode getNameScope ()
	{
	return nameScope;
	}


	// package private
	String getValue (String name)
	{
	Attr attr = (Attr) getNamedItem (name);

	if (attr == null)
	return "";
	else
	return attr.getValue ();
	}

	public Node getNamedItem (String name)
	{
	int length = list.size ();
	Node value;

	for (int i = 0; i < length; i++) {
	value = item (i);
	if (value.getNodeName ().equals (name))
	return value;
	}
	return null;
	}

	/**
	* <b>DOM2:</b>
	*/
	public Node getNamedItemNS(String namespaceURI, String localName) {
	for (int i = 0; i < list.size(); i++) {
	Node value = item(i);
	String iLocalName = value.getLocalName();
	if (iLocalName != null && iLocalName.equals(localName)) {
	String iNamespaceURI = value.getNamespaceURI();
	if (iNamespaceURI != null
	&& iNamespaceURI.equals(namespaceURI)) {
	return value;
	}
	}
	}
	return null;
	}

	public int getLength ()
	{
	return list.size ();
	}

	public Node item (int index)
	{
	if (index < 0 \|\| index >= list.size ())
	return null;
	return (Node) list.elementAt (index);
	}

	public Node removeNamedItem (String name)
	throws DOMException
	{
	int length = list.size ();
	Node value;

	if (readonly)
	throw new DomEx (DomEx.NO_MODIFICATION_ALLOWED_ERR);
	for (int i = 0; i < length; i++) {
	value = item (i);
	if (value.getNodeName ().equals (name)) {
	AttributeNode att = (AttributeNode) value;

	if (att.getDefaultValue () != null) {
	att = new AttributeNode (att);
	att.setOwnerDocument ((XmlDocument)
	nameScope.getOwnerDocument ());
	list.setElementAt (att, i);
	} else
	list.removeElementAt (i);

	att.setNameScope (null);
	return value;
	}
	}
	throw new DomEx (DomEx.NOT_FOUND_ERR);
	}

	/**
	* <b>DOM2:</b>
	*/
	public Node removeNamedItemNS(String namespaceURI, String localName)
	throws DOMException
	{
	if (readonly) {
	throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);
	}

	for (int i = 0; i < list.size(); i++) {
	Node value = item(i);
	String iLocalName = value.getLocalName();
	if (iLocalName != null && iLocalName.equals(localName)) {
	String iNamespaceURI = value.getNamespaceURI();
	if (iNamespaceURI != null
	&& iNamespaceURI.equals(namespaceURI)) {
	AttributeNode attr = (AttributeNode) value;
	if (attr.getDefaultValue() != null) {
	attr = new AttributeNode(attr);
	list.setElementAt(attr, i);
	} else {
	list.removeElementAt(i);
	}
	return value;
	}
	}
	}
	throw new DomEx(DomEx.NOT_FOUND_ERR);
	}

	public Node setNamedItem (Node value)
	throws DOMException
	{
	AttributeNode node;

	if (readonly)
	throw new DomEx (DomEx.NO_MODIFICATION_ALLOWED_ERR);
	if (!(value instanceof AttributeNode)
	\|\| value.getOwnerDocument ()
	!= nameScope.getOwnerDocument ())
	throw new DomEx (DomEx.WRONG_DOCUMENT_ERR);
	node = (AttributeNode)value;
	if (node.getNameScope () != null)
	throw new DomEx (DomEx.INUSE_ATTRIBUTE_ERR);

	int length = list.size ();
	AttributeNode oldValue;

	for (int i = 0; i < length; i++) {
	oldValue = (AttributeNode) item (i);
	if (oldValue.getNodeName ().equals (value.getNodeName ())) {
	if (oldValue.isReadonly ())
	throw new DomEx (DomEx.NO_MODIFICATION_ALLOWED_ERR);
	node.setNameScope (nameScope);
	list.setElementAt (value, i);
	oldValue.setNameScope (null);
	return oldValue;
	}
	}
	node.setNameScope (nameScope);
	list.addElement (value);
	return null;
	}

	/**
	* <b>DOM2:</b>
	* XXX spec allows Element nodes also, but this code assumes Attr nodes
	* only
	*/
	public Node setNamedItemNS(Node arg) throws DOMException {
	if (readonly) {
	throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);
	}

	AttributeNode attr = (AttributeNode) arg;
	if (attr.getOwnerElement() != null) {
	throw new DomEx(DomEx.INUSE_ATTRIBUTE_ERR);
	}

	for (int i = 0; i < list.size(); i++) {
	AttributeNode oldNode = (AttributeNode) item(i);
	String localName = oldNode.getLocalName();
	String namespaceURI = oldNode.getNamespaceURI();
	if (arg.getLocalName().equals(localName)
	&& arg.getNamespaceURI().equals(namespaceURI)) {
	// Found a matching node so replace it
	list.setElementAt(arg, i);
	return oldNode;
	}
	}

	// Append instead of replace
	list.addElement(arg);
	return null;
	}

	/**
	* Writes out the attribute list. Attributes known to have been
	* derived from the DTD are not (at this time) written out. Part
	* of writing standalone XML is first ensuring that all attributes
	* are flagged as being specified in the "printed" form (or else
	* are defaulted only in the internal DTD subset).
	*/
	public void writeXml (XmlWriteContext context) throws IOException
	{
	Writer out = context.getWriter ();
	int length = list.size ();
	AttributeNode tmp;

	for (int i = 0; i < length; i++) {
	tmp = (AttributeNode) list.elementAt (i);
	if (tmp.getSpecified ()) {
	out.write (' ');
	tmp.writeXml (context);
	}
	}
	}

	/**
	* Does nothing; this type of node has no children.
	*/
	public void writeChildrenXml (XmlWriteContext context) throws IOException
	{
	}

	public String toString ()
	{
	try {
	CharArrayWriter w = new CharArrayWriter ();
	XmlWriteContext x = new XmlWriteContext (w);
	writeXml (x);
	return w.toString ();

	} catch (IOException e) {
	return super.toString ();
	}
	}
	}