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 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
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 * distributed under the License is distributed on an "AS IS" BASIS,
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// $Id: NamespaceContext.java 446598 2006-09-15 12:55:40Z jeremias $

package javax.xml.namespace;

import java.util.Iterator;


Interface for read only XML Namespace context processing.


An XML Namespace has the properties:


    
  
  • Namespace URI:
      Namespace name expressed as a URI to which the prefix is bound
    • 
  
  • prefix: syntactically, this is the part of the attribute name
      following the XMLConstants.XMLNS_ATTRIBUTE
      ("xmlns") in the Namespace declaration
    • 



 example: <element xmlns:prefix="http://Namespace-name-URI">


All get*(*) methods operate in the current scope
for Namespace URI and prefix resolution.


Note that a Namespace URI can be bound to
multiple prefixes in the current scope.  This can
occur when multiple XMLConstants.XMLNS_ATTRIBUTE
("xmlns") Namespace declarations occur in the same Start-Tag and
refer to the same Namespace URI. e.g.


<element xmlns:prefix1="http://Namespace-name-URI"
         xmlns:prefix2="http://Namespace-name-URI">


This can also occur when the same Namespace URI is used in multiple
XMLConstants.XMLNS_ATTRIBUTE ("xmlns") Namespace
declarations in the logical parent element hierarchy.  e.g.


<parent xmlns:prefix1="http://Namespace-name-URI">
  <child xmlns:prefix2="http://Namespace-name-URI">
    ...
  </child>
</parent>



A prefix can only be bound to a single
Namespace URI in the current scope.


Author:Jeff Suttor
See Also:
Version:$Revision: 446598 $, $Date: 2006-09-15 08:55:40 -0400 (Fri, 15 Sep 2006) $
Since:1.5
/**
 * <p>Interface for read only XML Namespace context processing.</p>
 *
 * <p>An XML Namespace has the properties:</p>
 * <ul>
 *   <li>Namespace URI:
 *       Namespace name expressed as a URI to which the prefix is bound</li>
 *   <li>prefix: syntactically, this is the part of the attribute name
 *       following the <code>XMLConstants.XMLNS_ATTRIBUTE</code>
 *       ("xmlns") in the Namespace declaration</li>
 * </ul>
 * <p> example: <code>&lt;element xmlns:prefix="http://Namespace-name-URI"&gt;</code></p>
 *
 * <p>All <code>get*(*)</code> methods operate in the current scope
 * for Namespace URI and prefix resolution.</p>
 *
 * <p>Note that a Namespace URI can be bound to
 * <strong>multiple</strong> prefixes in the current scope.  This can
 * occur when multiple <code>XMLConstants.XMLNS_ATTRIBUTE</code>
 * ("xmlns") Namespace declarations occur in the same Start-Tag and
 * refer to the same Namespace URI. e.g.<br />
 * <pre>
 * &lt;element xmlns:prefix1="http://Namespace-name-URI"
 *          xmlns:prefix2="http://Namespace-name-URI"&gt;
 * </pre>
 * This can also occur when the same Namespace URI is used in multiple
 * <code>XMLConstants.XMLNS_ATTRIBUTE</code> ("xmlns") Namespace
 * declarations in the logical parent element hierarchy.  e.g.<br />
 * <pre>
 * &lt;parent xmlns:prefix1="http://Namespace-name-URI">
 *   &lt;child xmlns:prefix2="http://Namespace-name-URI"&gt;
 *     ...
 *   &lt;/child&gt;
 * &lt;/parent&gt;
 * </pre></p>
 *
 * <p>A prefix can only be bound to a <strong>single</strong>
 * Namespace URI in the current scope.</p>
 *
 * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
 * @version $Revision: 446598 $, $Date: 2006-09-15 08:55:40 -0400 (Fri, 15 Sep 2006) $
 * @see javax.xml.XMLConstants javax.XMLConstants for declarations of common XML values
 * @see <a href="http://www.w3.org/TR/xmlschema-2/#QName">XML Schema Part2: Datatypes</a>
 * @see <a href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">Namespaces in XML</a>
 * @see <a href="http://www.w3.org/XML/xml-names-19990114-errata">Namespaces in XML Errata</a>
 * @since 1.5
 */

public interface NamespaceContext {

    
Get Namespace URI bound to a prefix in the current scope.


When requesting a Namespace URI by prefix, the following
table describes the returned Namespace URI value for all
possible prefix values:


 
  
    

      
        getNamespaceURI(prefix)
        return value for specified prefixes
      
    

    

      prefix parameter
      Namespace URI return value
    

  
  
    

      DEFAULT_NS_PREFIX ("")
      default Namespace URI in the current scope or
        XMLConstants.NULL_NS_URI("")   
        when there is no default Namespace URI in the current scope
    

    

      bound prefix
      Namespace URI bound to prefix in current scope
    

    

      unbound prefix
      XMLConstants.NULL_NS_URI("") 
    

    

      XMLConstants.XML_NS_PREFIX ("xml")
      XMLConstants.XML_NS_URI
          ("http://www.w3.org/XML/1998/namespace")
    

    

      XMLConstants.XMLNS_ATTRIBUTE ("xmlns")
      XMLConstants.XMLNS_ATTRIBUTE_NS_URI
        ("http://www.w3.org/2000/xmlns/")
    

    

      null
      IllegalArgumentException is thrown
    

   


 

Params:
  • prefix – prefix to look up
Returns:Namespace URI bound to prefix in the current scope
/**
     * <p>Get Namespace URI bound to a prefix in the current scope.</p>
     *
     * <p>When requesting a Namespace URI by prefix, the following
     * table describes the returned Namespace URI value for all
     * possible prefix values:</p>
     *
     * <table border="2" rules="all" cellpadding="4"> 
     *   <thead>
     *     <tr>
     *       <td align="center" colspan="2">
     *         <code>getNamespaceURI(prefix)</code>
     *         return value for specified prefixes
     *       </td>
     *     </tr>
     *     <tr>
     *       <td>prefix parameter</td>
     *       <td>Namespace URI return value</td>
     *     </tr>
     *   </thead>
     *   <tbody>
     *     <tr>
     *       <td><code>DEFAULT_NS_PREFIX</code> ("")</td>
     *       <td>default Namespace URI in the current scope or
     *         <code>{@link javax.xml.XMLConstants#NULL_NS_URI XMLConstants.NULL_NS_URI("")}</code>   
     *         when there is no default Namespace URI in the current scope</td>
     *     </tr>
     *     <tr>
     *       <td>bound prefix</td>
     *       <td>Namespace URI bound to prefix in current scope</td>
     *     </tr>
     *     <tr>
     *       <td>unbound prefix</td>
     *       <td><code>{@link javax.xml.XMLConstants#NULL_NS_URI XMLConstants.NULL_NS_URI("")}</code> </td>
     *     </tr>
     *     <tr>
     *       <td><code>XMLConstants.XML_NS_PREFIX</code> ("xml")</td>
     *       <td><code>XMLConstants.XML_NS_URI</code>
     *           ("http://www.w3.org/XML/1998/namespace")</td>
     *     </tr>
     *     <tr>
     *       <td><code>XMLConstants.XMLNS_ATTRIBUTE</code> ("xmlns")</td>
     *       <td><code>XMLConstants.XMLNS_ATTRIBUTE_NS_URI</code>
     *         ("http://www.w3.org/2000/xmlns/")</td>
     *     </tr>
     *     <tr>
     *       <td><code>null</code></td>
     *       <td><code>IllegalArgumentException</code> is thrown</td>
     *     </tr>
     *    </tbody>
     * </table>
     *  
     * @param prefix prefix to look up
     * @return Namespace URI bound to prefix in the current scope
     */ 
    String getNamespaceURI(String prefix);
  
    
Get prefix bound to Namespace URI in the current scope.


To get all prefixes bound to a Namespace URI in the current scope, use getPrefixes(String namespaceURI).


When requesting a prefix by Namespace URI, the following
table describes the returned prefix value for all Namespace URI
values:



  
    

      
        getPrefix(namespaceURI) return value for
        specified Namespace URIs
      
    

    

      Namespace URI parameter
      prefix value returned
    

  
  
    

      <default Namespace URI>
      XMLConstants.DEFAULT_NS_PREFIX ("")
      
    

    

      bound Namespace URI
      prefix bound to Namespace URI in the current scope,
          if multiple prefixes are bound to the Namespace URI in
          the current scope, a single arbitrary prefix, whose
          choice is implementation dependent, is returned
    

    

      unbound Namespace URI
      null
    

    

      XMLConstants.XML_NS_URI
          ("http://www.w3.org/XML/1998/namespace")
      XMLConstants.XML_NS_PREFIX ("xml")
    

    

      XMLConstants.XMLNS_ATTRIBUTE_NS_URI
          ("http://www.w3.org/2000/xmlns/")
      XMLConstants.XMLNS_ATTRIBUTE ("xmlns")
    

    

      null
      IllegalArgumentException is thrown
    

  



Params:
  • namespaceURI – URI of Namespace to lookup
Returns:prefix bound to Namespace URI in current context
/**
     * <p>Get prefix bound to Namespace URI in the current scope.</p>
     *
     * <p>To get all prefixes bound to a Namespace URI in the current
     * scope, use {@link #getPrefixes(String namespaceURI)}.</p>
     *
     * <p>When requesting a prefix by Namespace URI, the following
     * table describes the returned prefix value for all Namespace URI
     * values:</p>
     *
     * <table border="2" rules="all" cellpadding="4">
     *   <thead>
     *     <tr>
     *       <td align="center" colspan="2">
     *         <code>getPrefix(namespaceURI)</code> return value for
     *         specified Namespace URIs
     *       </td>
     *     </tr>
     *     <tr>
     *       <td>Namespace URI parameter</td>
     *       <td>prefix value returned</td>
     *     </tr>
     *   </thead>
     *   <tbody>
     *     <tr>
     *       <td>&lt;default Namespace URI&gt;</td>
     *       <td><code>XMLConstants.DEFAULT_NS_PREFIX</code> ("")
     *       </td>
     *     </tr>
     *     <tr>
     *       <td>bound Namespace URI</td>
     *       <td>prefix bound to Namespace URI in the current scope,
     *           if multiple prefixes are bound to the Namespace URI in
     *           the current scope, a single arbitrary prefix, whose
     *           choice is implementation dependent, is returned</td>
     *     </tr>
     *     <tr>
     *       <td>unbound Namespace URI</td>
     *       <td><code>null</code></td>
     *     </tr>
     *     <tr>
     *       <td><code>XMLConstants.XML_NS_URI</code>
     *           ("http://www.w3.org/XML/1998/namespace")</td>
     *       <td><code>XMLConstants.XML_NS_PREFIX</code> ("xml")</td>
     *     </tr>
     *     <tr>
     *       <td><code>XMLConstants.XMLNS_ATTRIBUTE_NS_URI</code>
     *           ("http://www.w3.org/2000/xmlns/")</td>
     *       <td><code>XMLConstants.XMLNS_ATTRIBUTE</code> ("xmlns")</td>
     *     </tr>
     *     <tr>
     *       <td><code>null</code></td>
     *       <td><code>IllegalArgumentException</code> is thrown</td>
     *     </tr>
     *   </tbody>
     * </table>
     *
     * @param namespaceURI URI of Namespace to lookup
     * @return prefix bound to Namespace URI in current context
     */
    String getPrefix(String namespaceURI);

    
Get all prefixes bound to a Namespace URI in the current
scope.


An Iterator over String elements is returned in an arbitrary, implementation dependent, order.


The Iterator is
not modifiable.  e.g. the
remove() method will throw
UnsupportedOperationException.


When requesting prefixes by Namespace URI, the following
table describes the returned prefixes value for all Namespace
URI values:



  
    

      
        getPrefixes(namespaceURI) return value for
        specified Namespace URIs
    

    

      Namespace URI parameter
      prefixes value returned
    

  
  
    

      bound Namespace URI,
        including the <default Namespace URI>
      Iterator over prefixes bound to Namespace URI in
        the current scope in an arbitrary, implementation dependent,
        order
    

    

      unbound Namespace URI
      empty Iterator
    

    

      XMLConstants.XML_NS_URI
          ("http://www.w3.org/XML/1998/namespace")
      Iterator with one element set to
        XMLConstants.XML_NS_PREFIX ("xml")
    

    

      XMLConstants.XMLNS_ATTRIBUTE_NS_URI
          ("http://www.w3.org/2000/xmlns/")
      Iterator with one element set to
        XMLConstants.XMLNS_ATTRIBUTE ("xmlns")
    

    

      null
      IllegalArgumentException is thrown
    

  



Params:
  • namespaceURI – URI of Namespace to lookup
Returns:Iterator for all prefixes bound to the
Namespace URI in the current scope
/**
     * <p>Get all prefixes bound to a Namespace URI in the current
     * scope.</p>
     *
     * <p>An Iterator over String elements is returned in an arbitrary, <strong>implementation dependent</strong>, order.</p>
     *
     * <p><strong>The <code>Iterator</code> is
     * <em>not</em> modifiable.  e.g. the
     * <code>remove()</code> method will throw
     * <code>UnsupportedOperationException</code>.</strong></p>
     *
     * <p>When requesting prefixes by Namespace URI, the following
     * table describes the returned prefixes value for all Namespace
     * URI values:</p>
     *
     * <table border="2" rules="all" cellpadding="4">
     *   <thead>
     *     <tr>
     *       <td align="center" colspan="2"><code>
     *         getPrefixes(namespaceURI)</code> return value for
     *         specified Namespace URIs</td>
     *     </tr>
     *     <tr>
     *       <td>Namespace URI parameter</td>
     *       <td>prefixes value returned</td>
     *     </tr>
     *   </thead>
     *   <tbody>
     *     <tr>
     *       <td>bound Namespace URI,
     *         including the &lt;default Namespace URI&gt;</td>
     *       <td><code>Iterator</code> over prefixes bound to Namespace URI in
     *         the current scope in an arbitrary, <strong>implementation dependent</strong>,
     *         order</td>
     *     </tr>
     *     <tr>
     *       <td>unbound Namespace URI</td>
     *       <td>empty <code>Iterator</code></td>
     *     </tr>
     *     <tr>
     *       <td><code>XMLConstants.XML_NS_URI</code>
     *           ("http://www.w3.org/XML/1998/namespace")</td>
     *       <td><code>Iterator</code> with one element set to
     *         <code>XMLConstants.XML_NS_PREFIX</code> ("xml")</td>
     *     </tr>
     *     <tr>
     *       <td><code>XMLConstants.XMLNS_ATTRIBUTE_NS_URI</code>
     *           ("http://www.w3.org/2000/xmlns/")</td>
     *       <td><code>Iterator</code> with one element set to
     *         <code>XMLConstants.XMLNS_ATTRIBUTE</code> ("xmlns")</td>
     *     </tr>
     *     <tr>
     *       <td><code>null</code></td>
     *       <td><code>IllegalArgumentException</code> is thrown</td>
     *     </tr>
     *   </tbody>
     * </table>
     *
     * @param namespaceURI URI of Namespace to lookup
     * @return <code>Iterator</code> for all prefixes bound to the
     * Namespace URI in the current scope
     */
    Iterator getPrefixes(String namespaceURI);
}