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/* * Copyright (c) 2000, 2019, 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.parsers; import com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl; import javax.xml.validation.Schema; import org.xml.sax.SAXException; import org.xml.sax.SAXNotRecognizedException; import org.xml.sax.SAXNotSupportedException; /** * Defines a factory API that enables applications to configure and * obtain a SAX based parser to parse XML documents. * * @author Jeff Suttor * @author Neeraj Bajaj * * @since 1.4 */ public abstract class SAXParserFactory { private static final String DEFAULT_IMPL = "com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl"; /** * Should Parsers be validating? */ private boolean validating = false; /** * Should Parsers be namespace aware? */ private boolean namespaceAware = false; /** * Protected constructor to force use of {@link #newInstance()}. */ protected SAXParserFactory() { } /** * Creates a new NamespaceAware instance of the {@code SAXParserFactory} * builtin system-default implementation. Parsers produced by the factory * instance provides support for XML namespaces by default. * * @implSpec * In addition to creating a factory instance using the same process as * {@link #newDefaultInstance()}, this method must set NamespaceAware to true. * * @return a new instance of the {@code SAXParserFactory} builtin * system-default implementation. * * @since 13 */ public static SAXParserFactory newDefaultNSInstance() { return makeNSAware(new SAXParserFactoryImpl()); } /** * Creates a new NamespaceAware instance of a {@code SAXParserFactory}. * Parsers produced by the factory instance provides support for XML * namespaces by default. * * @implSpec * In addition to creating a factory instance using the same process as * {@link #newInstance()}, this method must set NamespaceAware to true. * * @return a new instance of the {@code SAXParserFactory} * * @throws FactoryConfigurationError in case of {@linkplain * java.util.ServiceConfigurationError service configuration error} * or if the implementation is not available or cannot be instantiated. * * @since 13 */ public static SAXParserFactory newNSInstance() { return makeNSAware(FactoryFinder.find(SAXParserFactory.class, DEFAULT_IMPL)); } /** * Creates a new NamespaceAware instance of a {@code SAXParserFactory} from * the class name. Parsers produced by the factory instance provides * support for XML namespaces by default. * * @implSpec * In addition to creating a factory instance using the same process as * {@link #newInstance(java.lang.String, java.lang.ClassLoader)}, this method * must set NamespaceAware to true. * * @param factoryClassName a fully qualified factory class name that provides * implementation of * {@code javax.xml.parsers.SAXParserFactory}. * * @param classLoader the {@code ClassLoader} used to load the factory class. * If it is {@code null}, the current {@code Thread}'s * context classLoader is used to load the factory class. * * @return a new instance of the {@code SAXParserFactory} * * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or * the factory class cannot be loaded, instantiated. * * @since 13 */ public static SAXParserFactory newNSInstance(String factoryClassName, ClassLoader classLoader) { return makeNSAware(FactoryFinder.newInstance(SAXParserFactory.class, factoryClassName, classLoader, false)); } /** * Creates a new instance of the {@code SAXParserFactory} builtin * system-default implementation. * * @return A new instance of the {@code SAXParserFactory} builtin * system-default implementation. * * @since 9 */ public static SAXParserFactory newDefaultInstance() { return new SAXParserFactoryImpl(); } /** * Obtain a new instance of a {@code SAXParserFactory}. This * static method creates a new factory instance * This method uses the following ordered lookup procedure to determine * the {@code SAXParserFactory} implementation class to * load: * <ul> * <li> * Use the {@code javax.xml.parsers.SAXParserFactory} system * property. * </li> * <li> * <p> * Use the configuration file "jaxp.properties". The file is in standard * {@link java.util.Properties} format and typically located in the * {@code conf} directory of the Java installation. It contains the fully qualified * name of the implementation class with the key being the system property * defined above. * <p> * The jaxp.properties file is read only once by the JAXP implementation * and its values are then cached for future use. If the file does not exist * when the first attempt is made to read from it, no further attempts are * made to check for its existence. It is not possible to change the value * of any property in jaxp.properties after it has been read for the first time. * </li> * <li> * <p> * Use the service-provider loading facility, defined by the * {@link java.util.ServiceLoader} class, to attempt to locate and load an * implementation of the service using the {@linkplain * java.util.ServiceLoader#load(java.lang.Class) default loading mechanism}: * the service-provider loading facility will use the {@linkplain * java.lang.Thread#getContextClassLoader() current thread's context class loader} * to attempt to load the service. If the context class * loader is null, the {@linkplain * ClassLoader#getSystemClassLoader() system class loader} will be used. * </li> * <li> * <p> * Otherwise, the {@linkplain #newDefaultInstance() system-default} * implementation is returned. * </li> * </ul> * * <p> * Once an application has obtained a reference to a * {@code SAXParserFactory} it can use the factory to * configure and obtain parser instances. * * * * <h4>Tip for Trouble-shooting</h4> * <p> * Setting the {@code jaxp.debug} system property will cause * this method to print a lot of debug messages * to {@code System.err} about what it is doing and where it is looking at. * * <p> * If you have problems loading {@link SAXParser}s, try: * <pre> * java -Djaxp.debug=1 YourProgram .... * </pre> * * * @return A new instance of a SAXParserFactory. * * @throws FactoryConfigurationError in case of {@linkplain * java.util.ServiceConfigurationError service configuration error} or if * the implementation is not available or cannot be instantiated. */ public static SAXParserFactory newInstance() { return FactoryFinder.find( /* The default property name according to the JAXP spec */ SAXParserFactory.class, /* The fallback implementation class name */ DEFAULT_IMPL); } /** * Obtain a new instance of a {@code SAXParserFactory} from class name. * This function is useful when there are multiple providers in the classpath. * It gives more control to the application as it can specify which provider * should be loaded. * * <p>Once an application has obtained a reference to a {@code SAXParserFactory} * it can use the factory to configure and obtain parser instances. * * * <h4>Tip for Trouble-shooting</h4> * <p>Setting the {@code jaxp.debug} system property will cause * this method to print a lot of debug messages * to {@code System.err} about what it is doing and where it is looking at. * * <p> * If you have problems, try: * <pre> * java -Djaxp.debug=1 YourProgram .... * </pre> * * @param factoryClassName fully qualified factory class name that provides implementation of {@code javax.xml.parsers.SAXParserFactory}. * * @param classLoader {@code ClassLoader} used to load the factory class. If {@code null} * current {@code Thread}'s context classLoader is used to load the factory class. * * @return New instance of a {@code SAXParserFactory} * * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or * the factory class cannot be loaded, instantiated. * * @see #newInstance() * * @since 1.6 */ public static SAXParserFactory newInstance(String factoryClassName, ClassLoader classLoader) { //do not fallback if given classloader can't find the class, throw exception return FactoryFinder.newInstance(SAXParserFactory.class, factoryClassName, classLoader, false); } private static SAXParserFactory makeNSAware(SAXParserFactory spf) { spf.setNamespaceAware(true); return spf; } /** * Creates a new instance of a SAXParser using the currently * configured factory parameters. * * @return A new instance of a SAXParser. * * @throws ParserConfigurationException if a parser cannot * be created which satisfies the requested configuration. * @throws SAXException for SAX errors. */ public abstract SAXParser newSAXParser() throws ParserConfigurationException, SAXException; /** * Specifies that the parser produced by this code will * provide support for XML namespaces. By default the value of this is set * to {@code false}. * * @param awareness true if the parser produced by this code will * provide support for XML namespaces; false otherwise. */ public void setNamespaceAware(boolean awareness) { this.namespaceAware = awareness; } /** * Specifies that the parser produced by this code will * validate documents as they are parsed. By default the value of this is * set to {@code false}. * * <p> * Note that "the validation" here means * <a href="http://www.w3.org/TR/REC-xml#proc-types">a validating * parser</a> as defined in the XML recommendation. * In other words, it essentially just controls the DTD validation. * (except the legacy two properties defined in JAXP 1.2.) * * <p> * To use modern schema languages such as W3C XML Schema or * RELAX NG instead of DTD, you can configure your parser to be * a non-validating parser by leaving the {@link #setValidating(boolean)} * method {@code false}, then use the {@link #setSchema(Schema)} * method to associate a schema to a parser. * * @param validating true if the parser produced by this code will * validate documents as they are parsed; false otherwise. */ public void setValidating(boolean validating) { this.validating = validating; } /** * Indicates whether or not the factory is configured to produce * parsers which are namespace aware. * * @return true if the factory is configured to produce * parsers which are namespace aware; false otherwise. */ public boolean isNamespaceAware() { return namespaceAware; } /** * Indicates whether or not the factory is configured to produce * parsers which validate the XML content during parse. * * @return true if the factory is configured to produce parsers which validate * the XML content during parse; false otherwise. */ public boolean isValidating() { return validating; } /** * Sets the particular feature in the underlying implementation of * org.xml.sax.XMLReader. * A list of the core features and properties can be found at * <a href="http://www.saxproject.org/">http://www.saxproject.org/</a> * * <p>All implementations are required to support the {@link javax.xml.XMLConstants#FEATURE_SECURE_PROCESSING} feature. * When the feature is * <ul> * <li> * {@code true}: the implementation will limit XML processing to conform to implementation limits. * Examples include entity expansion limits and XML Schema constructs that would consume large amounts of resources. * If XML processing is limited for security reasons, it will be reported via a call to the registered * {@link org.xml.sax.ErrorHandler#fatalError(SAXParseException exception)}. * See {@link SAXParser} {@code parse} methods for handler specification. * </li> * <li> * When the feature is {@code false}, the implementation will processing XML according to the XML specifications without * regard to possible implementation limits. * </li> * </ul> * * @param name The name of the feature to be set. * @param value The value of the feature to be set. * * @throws ParserConfigurationException if a parser cannot * be created which satisfies the requested configuration. * @throws SAXNotRecognizedException When the underlying XMLReader does * not recognize the property name. * @throws SAXNotSupportedException When the underlying XMLReader * recognizes the property name but doesn't support the * property. * @throws NullPointerException If the {@code name} parameter is null. * * @see org.xml.sax.XMLReader#setFeature */ public abstract void setFeature(String name, boolean value) throws ParserConfigurationException, SAXNotRecognizedException, SAXNotSupportedException; /** * * Returns the particular property requested for in the underlying * implementation of org.xml.sax.XMLReader. * * @param name The name of the property to be retrieved. * * @return Value of the requested property. * * @throws ParserConfigurationException if a parser cannot be created which satisfies the requested configuration. * @throws SAXNotRecognizedException When the underlying XMLReader does not recognize the property name. * @throws SAXNotSupportedException When the underlying XMLReader recognizes the property name but doesn't support the property. * * @see org.xml.sax.XMLReader#getProperty */ public abstract boolean getFeature(String name) throws ParserConfigurationException, SAXNotRecognizedException, SAXNotSupportedException; /** * Gets the {@link Schema} object specified through * the {@link #setSchema(Schema schema)} method. * * * @throws UnsupportedOperationException When implementation does not * override this method * * @return * the {@link Schema} object that was last set through * the {@link #setSchema(Schema)} method, or null * if the method was not invoked since a {@link SAXParserFactory} * is created. * * @since 1.5 */ public Schema getSchema() { throw new UnsupportedOperationException("This parser does not support specification \"" + this.getClass().getPackage().getSpecificationTitle() + "\" version \"" + this.getClass().getPackage().getSpecificationVersion() + "\""); } /** * Set the {@link Schema} to be used by parsers created * from this factory. * * <p>When a {@link Schema} is non-null, a parser will use a validator * created from it to validate documents before it passes information * down to the application. * * <p>When warnings/errors/fatal errors are found by the validator, the parser must * handle them as if those errors were found by the parser itself. * In other words, if the user-specified {@link org.xml.sax.ErrorHandler} * is set, it must receive those errors, and if not, they must be * treated according to the implementation specific * default error handling rules. * * <p>A validator may modify the SAX event stream (for example by * adding default values that were missing in documents), and a parser * is responsible to make sure that the application will receive * those modified event stream. * * <p>Initially, {@code null} is set as the {@link Schema}. * * <p>This processing will take effect even if * the {@link #isValidating()} method returns {@code false}. * * <p>It is an error to use * the {@code http://java.sun.com/xml/jaxp/properties/schemaSource} * property and/or the {@code http://java.sun.com/xml/jaxp/properties/schemaLanguage} * property in conjunction with a non-null {@link Schema} object. * Such configuration will cause a {@link SAXException} * exception when those properties are set on a {@link SAXParser}. * * <h4>Note for implementors</h4> * <p> * A parser must be able to work with any {@link Schema} * implementation. However, parsers and schemas are allowed * to use implementation-specific custom mechanisms * as long as they yield the result described in the specification. * * @param schema {@code Schema} to use, {@code null} to remove a schema. * * @throws UnsupportedOperationException When implementation does not * override this method * * @since 1.5 */ public void setSchema(Schema schema) { throw new UnsupportedOperationException("This parser does not support specification \"" + this.getClass().getPackage().getSpecificationTitle() + "\" version \"" + this.getClass().getPackage().getSpecificationVersion() + "\""); } /** * Set state of XInclude processing. * * <p>If XInclude markup is found in the document instance, should it be * processed as specified in <a href="http://www.w3.org/TR/xinclude/"> * XML Inclusions (XInclude) Version 1.0</a>. * * <p>XInclude processing defaults to {@code false}. * * @param state Set XInclude processing to {@code true} or * {@code false} * * @throws UnsupportedOperationException When implementation does not * override this method * * @since 1.5 */ public void setXIncludeAware(final boolean state) { if (state) { throw new UnsupportedOperationException(" setXIncludeAware " + "is not supported on this JAXP" + " implementation or earlier: " + this.getClass()); } } /** * Get state of XInclude processing. * * @return current state of XInclude processing * * @throws UnsupportedOperationException When implementation does not * override this method * * @since 1.5 */ public boolean isXIncludeAware() { throw new UnsupportedOperationException("This parser does not support specification \"" + this.getClass().getPackage().getSpecificationTitle() + "\" version \"" + this.getClass().getPackage().getSpecificationVersion() + "\""); } }