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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.DocumentBuilderFactoryImpl; import javax.xml.validation.Schema; /** * Defines a factory API that enables applications to obtain a * parser that produces DOM object trees from XML documents. * * @author Jeff Suttor * @author Neeraj Bajaj * * @since 1.4 */ public abstract class DocumentBuilderFactory { private static final String DEFAULT_IMPL = "com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl"; private boolean validating = false; private boolean namespaceAware = false; private boolean whitespace = false; private boolean expandEntityRef = true; private boolean ignoreComments = false; private boolean coalescing = false; /** * Protected constructor to prevent instantiation. * Use {@link #newInstance()}. */ protected DocumentBuilderFactory() { } /** * Creates a new NamespaceAware instance of the {@code DocumentBuilderFactory} * 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 DocumentBuilderFactory} builtin * system-default implementation. * * @since 13 */ public static DocumentBuilderFactory newDefaultNSInstance() { return makeNSAware(new DocumentBuilderFactoryImpl()); } /** * Creates a new NamespaceAware instance of a {@code DocumentBuilderFactory}. * 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 a {@code DocumentBuilderFactory} * * @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 DocumentBuilderFactory newNSInstance() { return makeNSAware(FactoryFinder.find(DocumentBuilderFactory.class, DEFAULT_IMPL)); } /** * Creates a new NamespaceAware instance of a {@code DocumentBuilderFactory} * 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.DocumentBuilderFactory}. * * @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 a {@code DocumentBuilderFactory} * * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or * the factory class cannot be loaded, instantiated. * * @since 13 */ public static DocumentBuilderFactory newNSInstance(String factoryClassName, ClassLoader classLoader) { return makeNSAware( FactoryFinder.newInstance(DocumentBuilderFactory.class, factoryClassName, classLoader, false)); } /** * Creates a new instance of the {@code DocumentBuilderFactory} builtin * system-default implementation. * * @return A new instance of the {@code DocumentBuilderFactory} builtin * system-default implementation. * * @since 9 */ public static DocumentBuilderFactory newDefaultInstance() { return new DocumentBuilderFactoryImpl(); } /** * Obtain a new instance of a * {@code DocumentBuilderFactory}. This static method creates * a new factory instance. * This method uses the following ordered lookup procedure to determine * the {@code DocumentBuilderFactory} implementation class to * load: * <ul> * <li> * Use the {@code javax.xml.parsers.DocumentBuilderFactory} 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 DocumentBuilderFactory} 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 DocumentBuilder}s, try: * <pre> * java -Djaxp.debug=1 YourProgram .... * </pre> * * @return New instance of a {@code DocumentBuilderFactory} * * @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 DocumentBuilderFactory newInstance() { return FactoryFinder.find( /* The default property name according to the JAXP spec */ DocumentBuilderFactory.class, // "javax.xml.parsers.DocumentBuilderFactory" /* The fallback implementation class name */ DEFAULT_IMPL); } /** * Obtain a new instance of a {@code DocumentBuilderFactory} 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 DocumentBuilderFactory} * 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.DocumentBuilderFactory}. * * @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 DocumentBuilderFactory} * * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or * the factory class cannot be loaded, instantiated. * * @see #newInstance() * * @since 1.6 */ public static DocumentBuilderFactory newInstance(String factoryClassName, ClassLoader classLoader) { //do not fallback if given classloader can't find the class, throw exception return FactoryFinder.newInstance(DocumentBuilderFactory.class, factoryClassName, classLoader, false); } private static DocumentBuilderFactory makeNSAware(DocumentBuilderFactory dbf) { dbf.setNamespaceAware(true); return dbf; } /** * Creates a new instance of a {@link javax.xml.parsers.DocumentBuilder} * using the currently configured parameters. * * @return A new instance of a DocumentBuilder. * * @throws ParserConfigurationException if a DocumentBuilder * cannot be created which satisfies the configuration requested. */ public abstract DocumentBuilder newDocumentBuilder() throws ParserConfigurationException; /** * 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 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 will validate documents * as they are parsed; false otherwise. */ public void setValidating(boolean validating) { this.validating = validating; } /** * Specifies that the parsers created by this factory must eliminate * whitespace in element content (sometimes known loosely as * 'ignorable whitespace') when parsing XML documents (see XML Rec * 2.10). Note that only whitespace which is directly contained within * element content that has an element only content model (see XML * Rec 3.2.1) will be eliminated. Due to reliance on the content model * this setting requires the parser to be in validating mode. By default * the value of this is set to {@code false}. * * @param whitespace true if the parser created must eliminate whitespace * in the element content when parsing XML documents; * false otherwise. */ public void setIgnoringElementContentWhitespace(boolean whitespace) { this.whitespace = whitespace; } /** * Specifies that the parser produced by this code will * expand entity reference nodes. By default the value of this is set to * {@code true} * * @param expandEntityRef true if the parser produced will expand entity * reference nodes; false otherwise. */ public void setExpandEntityReferences(boolean expandEntityRef) { this.expandEntityRef = expandEntityRef; } /** * Specifies that the parser produced by this code will * ignore comments. By default the value of this is set to {@code false}. * * @param ignoreComments {@code boolean} value to ignore comments during processing */ public void setIgnoringComments(boolean ignoreComments) { this.ignoreComments = ignoreComments; } /** * Specifies that the parser produced by this code will * convert CDATA nodes to Text nodes and append it to the * adjacent (if any) text node. By default the value of this is set to * {@code false} * * @param coalescing true if the parser produced will convert CDATA nodes * to Text nodes and append it to the adjacent (if any) * text node; false otherwise. */ public void setCoalescing(boolean coalescing) { this.coalescing = coalescing; } /** * 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; } /** * Indicates whether or not the factory is configured to produce * parsers which ignore ignorable whitespace in element content. * * @return true if the factory is configured to produce parsers * which ignore ignorable whitespace in element content; * false otherwise. */ public boolean isIgnoringElementContentWhitespace() { return whitespace; } /** * Indicates whether or not the factory is configured to produce * parsers which expand entity reference nodes. * * @return true if the factory is configured to produce parsers * which expand entity reference nodes; false otherwise. */ public boolean isExpandEntityReferences() { return expandEntityRef; } /** * Indicates whether or not the factory is configured to produce * parsers which ignores comments. * * @return true if the factory is configured to produce parsers * which ignores comments; false otherwise. */ public boolean isIgnoringComments() { return ignoreComments; } /** * Indicates whether or not the factory is configured to produce * parsers which converts CDATA nodes to Text nodes and appends it to * the adjacent (if any) Text node. * * @return true if the factory is configured to produce parsers * which converts CDATA nodes to Text nodes and appends it to * the adjacent (if any) Text node; false otherwise. */ public boolean isCoalescing() { return coalescing; } /** * Allows the user to set specific attributes on the underlying * implementation. * <p> * All implementations that implement JAXP 1.5 or newer are required to * support the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} and * {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} properties. * * <ul> * <li> * Setting the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property * restricts the access to external DTDs, external Entity References to the * protocols specified by the property. * If access is denied during parsing due to the restriction of this property, * {@link org.xml.sax.SAXException} will be thrown by the parse methods defined by * {@link javax.xml.parsers.DocumentBuilder}. * </li> * <li> * Setting the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} property * restricts the access to external Schema set by the schemaLocation attribute to * the protocols specified by the property. If access is denied during parsing * due to the restriction of this property, {@link org.xml.sax.SAXException} * will be thrown by the parse methods defined by * {@link javax.xml.parsers.DocumentBuilder}. * </li> * </ul> * * @param name The name of the attribute. * @param value The value of the attribute. * * @throws IllegalArgumentException thrown if the underlying * implementation doesn't recognize the attribute. */ public abstract void setAttribute(String name, Object value) throws IllegalArgumentException; /** * Allows the user to retrieve specific attributes on the underlying * implementation. * * @param name The name of the attribute. * * @return value The value of the attribute. * * @throws IllegalArgumentException thrown if the underlying * implementation doesn't recognize the attribute. */ public abstract Object getAttribute(String name) throws IllegalArgumentException; /** * Set a feature for this {@code DocumentBuilderFactory} * and {@code DocumentBuilder}s created by this factory. * * <p> * Feature names are fully qualified {@link java.net.URI}s. * Implementations may define their own features. * A {@link ParserConfigurationException} is thrown if this {@code DocumentBuilderFactory} or the * {@code DocumentBuilder}s it creates cannot support the feature. * It is possible for a {@code DocumentBuilderFactory} to expose a feature value but be unable to change its state. * * * <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 DocumentBuilder#setErrorHandler(org.xml.sax.ErrorHandler errorHandler)}. * </li> * <li> * {@code false}: the implementation will processing XML according to the XML specifications without * regard to possible implementation limits. * </li> * </ul> * * @param name Feature name. * @param value Is feature state {@code true} or {@code false}. * * @throws ParserConfigurationException if this {@code DocumentBuilderFactory} or the {@code DocumentBuilder}s * it creates cannot support this feature. * @throws NullPointerException If the {@code name} parameter is null. * @since 1.5 */ public abstract void setFeature(String name, boolean value) throws ParserConfigurationException; /** * Get the state of the named feature. * * <p> * Feature names are fully qualified {@link java.net.URI}s. * Implementations may define their own features. * An {@link ParserConfigurationException} is thrown if this {@code DocumentBuilderFactory} or the * {@code DocumentBuilder}s it creates cannot support the feature. * It is possible for an {@code DocumentBuilderFactory} to expose a feature value but be unable to change its state. * * @param name Feature name. * * @return State of the named feature. * * @throws ParserConfigurationException if this {@code DocumentBuilderFactory} * or the {@code DocumentBuilder}s it creates cannot support this feature. * @since 1.5 */ public abstract boolean getFeature(String name) throws ParserConfigurationException; /** * Gets the {@link Schema} object specified through * the {@link #setSchema(Schema schema)} 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 DocumentBuilderFactory} * is created. * * @throws UnsupportedOperationException When implementation does not * override this method. * * @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 errors are found by the validator, the parser is responsible * to report them to the user-specified {@link org.xml.sax.ErrorHandler} * (or if the error handler is not set, ignore them or throw them), just * like any other errors 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 outcome of a parse (for example by * adding default values that were missing in documents), and a parser * is responsible to make sure that the application will receive * modified DOM trees. * * <p> * Initially, 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 {@link Schema} object. * Such configuration will cause a {@link ParserConfigurationException} * exception when the {@link #newDocumentBuilder()} is invoked. * * * <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 or {@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() + "\""); } }