Java tutorial
/* * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.xml; /** * <p>Utility class to contain basic XML values as constants. * * @author Jeff Suttor * @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/TR/xmlschema-1/">XML Schema Part 1: Structures</a> * @since 1.5 **/ public final class XMLConstants { /** * Private constructor to prevent instantiation. */ private XMLConstants() { } /** * Namespace URI to use to represent that there is no Namespace. * * <p>Defined by the Namespace specification to be "". * * @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. * * <p>Defined by the XML specification to be "". * * @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. * * <p>Defined by the XML specification to be * "{@code http://www.w3.org/XML/1998/namespace}". * * @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. * * <p>Defined by the XML specification to be "{@code xml}". * * @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, {@link #XMLNS_ATTRIBUTE * XMLConstants.XMLNS_ATTRIBUTE}, Namespace name URI. * * <p>Defined by the XML specification to be * "{@code http://www.w3.org/2000/xmlns/}". * * @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_NS_URI = "http://www.w3.org/2000/xmlns/"; /** * The official XML attribute used for specifying XML Namespace * declarations. * * <p>It is <strong><em>NOT</em></strong> valid to use as a * prefix. Defined by the XML specification to be * "{@code xmlns}". * * @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. * * <p>Defined to be "{@code http://www.w3.org/2001/XMLSchema}". * * @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. * * <p>Defined to be "{@code http://www.w3.org/2001/XMLSchema-instance}". * * @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. * * <p>Defined to be "{@code http://www.w3.org/2003/11/xpath-datatypes}". * * @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. * * <p>Since not formally defined by any existing standard, arbitrarily define to be "{@code http://www.w3.org/TR/REC-xml}". */ public static final String XML_DTD_NS_URI = "http://www.w3.org/TR/REC-xml"; /** * RELAX NG Namespace URI. * * <p>Defined to be "{@code http://relaxng.org/ns/structure/1.0}". * * @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. * * <ul> * <li> * {@code true} 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} instructs the implementation to process XML in accordance with 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"; /** * Property: accessExternalDTD * * <p> * Restrict access to external DTDs and external Entity References to the protocols specified. * If access is denied due to the restriction of this property, a runtime exception that * is specific to the context is thrown. In the case of {@link javax.xml.parsers.SAXParser} * for example, {@link org.xml.sax.SAXException} is thrown. * * <p> * <b>Value: </b> a list of protocols separated by comma. A protocol is the scheme portion of a * {@link java.net.URI}, or in the case of the JAR protocol, "jar" plus the scheme portion * separated by colon. * A scheme is defined as: * * <blockquote> * scheme = alpha *( alpha | digit | "+" | "-" | "." )<br> * where alpha = a-z and A-Z.<br><br> * * And the JAR protocol:<br> * * jar[:scheme]<br><br> * * Protocols including the keyword "jar" are case-insensitive. Any whitespaces as defined by * {@link java.lang.Character#isSpaceChar } in the value will be ignored. * Examples of protocols are file, http, jar:file. * * </blockquote> * *<p> * <b>Default value:</b> The default value is implementation specific and therefore not specified. * The following options are provided for consideration: * <blockquote> * <UL> * <LI>an empty string to deny all access to external references;</LI> * <LI>a specific protocol, such as file, to give permission to only the protocol;</LI> * <LI>the keyword "all" to grant permission to all protocols.</LI> * </UL><br> * When FEATURE_SECURE_PROCESSING is enabled, it is recommended that implementations * restrict external connections by default, though this may cause problems for applications * that process XML/XSD/XSL with external references. * </blockquote> * * <p> * <b>Granting all access:</b> the keyword "all" grants permission to all protocols. * * <p> * <b>System Property:</b> The value of this property can be set or overridden by * system property {@code javax.xml.accessExternalDTD}. * * * <p> * <b>jaxp.properties:</b> This configuration file is in standard * {@link java.util.Properties} format and typically located in the {@code conf} * directory of the Java installation. If the file exists and the system * property is specified, its value will be used to override the default * of the property. * * * @since 1.7 */ public static final String ACCESS_EXTERNAL_DTD = "http://javax.xml.XMLConstants/property/accessExternalDTD"; /** * <p>Property: accessExternalSchema</p> * * <p> * Restrict access to the protocols specified for external reference set by the * schemaLocation attribute, Import and Include element. If access is denied * due to the restriction of this property, a runtime exception that is specific * to the context is thrown. In the case of {@link javax.xml.validation.SchemaFactory} * for example, org.xml.sax.SAXException is thrown. * * <p> * <b>Value:</b> a list of protocols separated by comma. A protocol is the scheme portion of a * {@link java.net.URI}, or in the case of the JAR protocol, "jar" plus the scheme portion * separated by colon. * A scheme is defined as: * * <blockquote> * scheme = alpha *( alpha | digit | "+" | "-" | "." )<br> * where alpha = a-z and A-Z.<br><br> * * And the JAR protocol:<br> * * jar[:scheme]<br><br> * * Protocols including the keyword "jar" are case-insensitive. Any whitespaces as defined by * {@link java.lang.Character#isSpaceChar } in the value will be ignored. * Examples of protocols are file, http, jar:file. * * </blockquote> * * <p> * <b>Default value:</b> The default value is implementation specific and therefore not specified. * The following options are provided for consideration: * <blockquote> * <UL> * <LI>an empty string to deny all access to external references;</LI> * <LI>a specific protocol, such as file, to give permission to only the protocol;</LI> * <LI>the keyword "all" to grant permission to all protocols.</LI> * </UL><br> * When FEATURE_SECURE_PROCESSING is enabled, it is recommended that implementations * restrict external connections by default, though this may cause problems for applications * that process XML/XSD/XSL with external references. * </blockquote> * * <p> * <b>Granting all access:</b> the keyword "all" grants permission to all protocols. * * <p> * <b>System Property:</b> The value of this property can be set or overridden by * system property {@code javax.xml.accessExternalSchema} * * <p> * <b>jaxp.properties:</b> This configuration file is in standard * {@link java.util.Properties} format and typically located in the {@code conf} * directory of the Java installation. If the file exists and the system * property is specified, its value will be used to override the default * of the property. * * @since 1.7 */ public static final String ACCESS_EXTERNAL_SCHEMA = "http://javax.xml.XMLConstants/property/accessExternalSchema"; /** * Property: accessExternalStylesheet * * <p> * Restrict access to the protocols specified for external references set by the * stylesheet processing instruction, Import and Include element, and document function. * If access is denied due to the restriction of this property, a runtime exception * that is specific to the context is thrown. In the case of constructing new * {@link javax.xml.transform.Transformer} for example, * {@link javax.xml.transform.TransformerConfigurationException} * will be thrown by the {@link javax.xml.transform.TransformerFactory}. * * <p> * <b>Value:</b> a list of protocols separated by comma. A protocol is the scheme portion of a * {@link java.net.URI}, or in the case of the JAR protocol, "jar" plus the scheme portion * separated by colon. * A scheme is defined as: * * <blockquote> * scheme = alpha *( alpha | digit | "+" | "-" | "." )<br> * where alpha = a-z and A-Z.<br><br> * * And the JAR protocol:<br> * * jar[:scheme]<br><br> * * Protocols including the keyword "jar" are case-insensitive. Any whitespaces as defined by * {@link java.lang.Character#isSpaceChar } in the value will be ignored. * Examples of protocols are file, http, jar:file. * * </blockquote> * * <p> * <b>Default value:</b> The default value is implementation specific and therefore not specified. * The following options are provided for consideration: * <blockquote> * <UL> * <LI>an empty string to deny all access to external references;</LI> * <LI>a specific protocol, such as file, to give permission to only the protocol;</LI> * <LI>the keyword "all" to grant permission to all protocols.</LI> * </UL><br> * When FEATURE_SECURE_PROCESSING is enabled, it is recommended that implementations * restrict external connections by default, though this may cause problems for applications * that process XML/XSD/XSL with external references. * </blockquote> * * <p> * <b>Granting all access:</b> the keyword "all" grants permission to all protocols. * * <p> * <b>System Property:</b> The value of this property can be set or overridden by * system property {@code javax.xml.accessExternalStylesheet} * * <p> * <b>jaxp.properties:</b> This configuration file is in standard * {@link java.util.Properties} format and typically located in the {@code conf} * directory of the Java installation. If the file exists and the system * property is specified, its value will be used to override the default * of the property. * * @since 1.7 */ public static final String ACCESS_EXTERNAL_STYLESHEET = "http://javax.xml.XMLConstants/property/accessExternalStylesheet"; /** * Feature: useCatalog * * <p> * Instructs XML processors to use XML Catalogs to resolve entity references. * Catalogs may be set through JAXP factories, system properties, or * jaxp.properties by using the {@code javax.xml.catalog.files} property * defined in {@link javax.xml.catalog.CatalogFeatures}. * The following code enables Catalog on SAX parser: * <pre>{@code * SAXParserFactory spf = SAXParserFactory.newInstance(); * spf.setFeature(XMLConstants.USE_CATALOG, true); * SAXParser parser = spf.newSAXParser(); * parser.setProperty(CatalogFeatures.Feature.FILES.getPropertyName(), "catalog.xml"); * }</pre> * * <p> * <b>Value:</b> a boolean. If the value is true, and a catalog is set, * the XML parser will resolve external references using * {@link javax.xml.catalog.CatalogResolver}. If the value is false, * XML Catalog is ignored even if one is set. The default value is true. * * <p> * <b>System Property:</b> The value of this property can be set or overridden by * system property {@code javax.xml.useCatalog} * * <p> * <b>jaxp.properties:</b> This configuration file is in standard * {@link java.util.Properties} format and typically located in the {@code conf} * directory of the Java installation. If the file exists and the system * property is specified, its value will be used to override the default * value of the property. * * @since 9 */ public static final String USE_CATALOG = "http://javax.xml.XMLConstants/feature/useCatalog"; }