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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * 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
 * 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.
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// $Id: XMLConstants.java 584477 2007-10-14 02:44:03Z mrglavas $

package javax.xml;


Utility class to contain basic XML values as constants.


Author:Jeff Suttor
See Also:
Version:$Revision: 584477 $, $Date: 2007-10-13 22:44:03 -0400 (Sat, 13 Oct 2007) $
Since:1.5
/**
 * <p>Utility class to contain basic XML values as constants.</p>
 *
 * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
 * @version $Revision: 584477 $, $Date: 2007-10-13 22:44:03 -0400 (Sat, 13 Oct 2007) $
 * @see <a href="http://www.w3.org/TR/xml11/">Extensible Markup Language (XML) 1.1</a>
 * @see <a href="http://www.w3.org/TR/REC-xml">Extensible Markup Language (XML) 1.0 (Second Edition)</a>
 * @see <a href="http://www.w3.org/XML/xml-V10-2e-errata">XML 1.0 Second Edition Specification Errata</a>
 * @see <a href="http://www.w3.org/TR/xml-names11/">Namespaces in XML 1.1</a>
 * @see <a href="http://www.w3.org/TR/REC-xml-names">Namespaces in XML</a>
 * @see <a href="http://www.w3.org/XML/xml-names-19990114-errata">Namespaces in XML Errata</a>
 * @see <a href="http://www.w3.org/TR/xmlschema-1/">XML Schema Part 1: Structures</a>
 * @since 1.5
 **/
public final class XMLConstants {

    
Private constructor to prevent instantiation.


/**
     * <p>Private constructor to prevent instantiation.</p>
     */
    private XMLConstants() {
    }

    
Namespace URI to use to represent that there is no Namespace.


Defined by the Namespace specification to be "".


See Also:
/**
     * <p>Namespace URI to use to represent that there is no Namespace.</p>
     *
     * <p>Defined by the Namespace specification to be "".</p>
     *
     * @see <a href="http://www.w3.org/TR/REC-xml-names/#defaulting">
     * Namespaces in XML, 5.2 Namespace Defaulting</a>
     */
    public static final String NULL_NS_URI = "";

    
Prefix to use to represent the default XML Namespace.


Defined by the XML specification to be "".


See Also:
/**
     * <p>Prefix to use to represent the default XML Namespace.</p>
     *
     * <p>Defined by the XML specification to be "".</p>
     *
     * @see <a
     * href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
     * Namespaces in XML, 3. Qualified Names</a>
     */
    public static final String DEFAULT_NS_PREFIX = "";

    
The official XML Namespace name URI.


Defined by the XML specification to be
"http://www.w3.org/XML/1998/namespace".


See Also:
/**
     * <p>The official XML Namespace name URI.</p>
     *
     * <p>Defined by the XML specification to be
     * "<code>http://www.w3.org/XML/1998/namespace</code>".</p>
     *
     * @see <a
     * href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
     * Namespaces in XML, 3. Qualified Names</a>
     */
    public static final String XML_NS_URI =
        "http://www.w3.org/XML/1998/namespace";

    
The official XML Namespace prefix.


Defined by the XML specification to be "xml".


See Also:
/**
     * <p>The official XML Namespace prefix.</p>
     *
     * <p>Defined by the XML specification to be "<code>xml</code>".</p>
     *
     * @see <a
     * href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
     * Namespaces in XML, 3. Qualified Names<</a>
     */
    public static final String XML_NS_PREFIX = "xml";

    
The official XML attribute used for specifying XML Namespace declarations, 
XMLConstants.XMLNS_ATTRIBUTE, Namespace name URI.


Defined by the XML specification to be
"http://www.w3.org/2000/xmlns/".


See Also:
/**
     * <p>The official XML attribute used for specifying XML Namespace
     * declarations, {@link #XMLNS_ATTRIBUTE
     * XMLConstants.XMLNS_ATTRIBUTE}, Namespace name URI.</p>
     *
     * <p>Defined by the XML specification to be
     * "<code>http://www.w3.org/2000/xmlns/</code>".</p>
     *
     * @see <a
     * href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
     * Namespaces in XML, 3. Qualified Names</a>
     * @see <a
     * href="http://www.w3.org/XML/xml-names-19990114-errata/">
     * Namespaces in XML Errata</a>
     */
    public static final String XMLNS_ATTRIBUTE_NS_URI =
        "http://www.w3.org/2000/xmlns/";

    
The official XML attribute used for specifying XML Namespace
declarations.


It is NOT valid to use as a
prefix.  Defined by the XML specification to be
"xmlns".


See Also:
/**
     * <p>The official XML attribute used for specifying XML Namespace
     * declarations.</p>
     *
     * <p>It is <strong><em>NOT</em></strong> valid to use as a
     * prefix.  Defined by the XML specification to be
     * "<code>xmlns</code>".</p>
     *
     * @see <a
     * href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
     * Namespaces in XML, 3. Qualified Names</a>
     */
    public static final String XMLNS_ATTRIBUTE = "xmlns";

    
W3C XML Schema Namespace URI.


Defined to be "http://www.w3.org/2001/XMLSchema".

See Also:
/**
     * <p>W3C XML Schema Namespace URI.</p>
     * 
     * <p>Defined to be "<code>http://www.w3.org/2001/XMLSchema</code>".
     * 
     * @see <a href=
     *  "http://www.w3.org/TR/xmlschema-1/#Instance_Document_Constructions">
     *  XML Schema Part 1:
     *  Structures, 2.6 Schema-Related Markup in Documents Being Validated</a>
     */
    public static final String W3C_XML_SCHEMA_NS_URI =
        "http://www.w3.org/2001/XMLSchema";

    
W3C XML Schema Instance Namespace URI.


Defined to be "http://www.w3.org/2001/XMLSchema-instance".


See Also:
/**
     * <p>W3C XML Schema Instance Namespace URI.</p>
     * 
     * <p>Defined to be "<code>http://www.w3.org/2001/XMLSchema-instance</code>".</p>
     * 
     * @see <a href=
     *  "http://www.w3.org/TR/xmlschema-1/#Instance_Document_Constructions">
     *  XML Schema Part 1:
     *  Structures, 2.6 Schema-Related Markup in Documents Being Validated</a>
     */
    public static final String W3C_XML_SCHEMA_INSTANCE_NS_URI =
        "http://www.w3.org/2001/XMLSchema-instance";

    
W3C XPath Datatype Namespace URI.


Defined to be "http://www.w3.org/2003/11/xpath-datatypes".


See Also:
/**
     * <p>W3C XPath Datatype Namespace URI.</p>
     * 
     * <p>Defined to be "<code>http://www.w3.org/2003/11/xpath-datatypes</code>".</p>
     * 
     * @see <a href="http://www.w3.org/TR/xpath-datamodel">XQuery 1.0 and XPath 2.0 Data Model</a>
     */
    public static final String W3C_XPATH_DATATYPE_NS_URI = "http://www.w3.org/2003/11/xpath-datatypes";

    
XML Document Type Declaration Namespace URI as an arbitrary value.


Since not formally defined by any existing standard, arbitrarily define to be "http://www.w3.org/TR/REC-xml".

/**
     * <p>XML Document Type Declaration Namespace URI as an arbitrary value.</p>
     * 
     * <p>Since not formally defined by any existing standard, arbitrarily define to be "<code>http://www.w3.org/TR/REC-xml</code>".
     */
    public static final String XML_DTD_NS_URI = "http://www.w3.org/TR/REC-xml";

    
RELAX NG Namespace URI.


Defined to be "http://relaxng.org/ns/structure/1.0".


See Also:
/**
     * <p>RELAX NG Namespace URI.</p>
     * 
     * <p>Defined to be "<code>http://relaxng.org/ns/structure/1.0</code>".</p>
     * 
     * @see <a href="http://relaxng.org/spec-20011203.html">RELAX NG Specification</a>
     */
    public static final String RELAXNG_NS_URI = "http://relaxng.org/ns/structure/1.0";

    
Feature for secure processing.


    
  
  • 
    true instructs the implementation to process XML securely.
    This may set limits on XML constructs to avoid conditions such as denial of service attacks.
  
    • 
  
  • 
    false instructs the implementation to process XML according to the letter of the XML specifications
    ignoring security issues such as limits on XML constructs to avoid conditions such as denial of service attacks.
  
    • 



/**
     * <p>Feature for secure processing.</p>
     * 
     * <ul>
     *   <li>
     *     <code>true</code> instructs the implementation to process XML securely.
     *     This may set limits on XML constructs to avoid conditions such as denial of service attacks.
     *   </li>
     *   <li>
     *     <code>false</code> instructs the implementation to process XML according to the letter of the XML specifications
     *     ignoring security issues such as limits on XML constructs to avoid conditions such as denial of service attacks.
     *   </li>
     * </ul>
     */    
    public static final String FEATURE_SECURE_PROCESSING = "http://javax.xml.XMLConstants/feature/secure-processing";
}