* 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/";

    /**
     * <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";
    
    /**
     * <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";

    /**
     * <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";

	/**
	 * <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";

    /**
     * <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";

	/**
	 * <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";
	
	/**
	 * <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 acording the letter of the XML specifications

	 *     ingoring 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";

}