Java tutorial
/* * Copyright (c) 2003, 2017, 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.validation; import com.sun.org.apache.xerces.internal.jaxp.validation.XMLSchemaFactory; import java.io.File; import java.net.URL; import javax.xml.transform.Source; import javax.xml.transform.stream.StreamSource; import jdk.xml.internal.SecuritySupport; import org.w3c.dom.ls.LSResourceResolver; import org.xml.sax.ErrorHandler; import org.xml.sax.SAXException; import org.xml.sax.SAXNotRecognizedException; import org.xml.sax.SAXNotSupportedException; import org.xml.sax.SAXParseException; /** * Factory that creates {@link Schema} objects. Entry-point to * the validation API. * * <p> * {@link SchemaFactory} is a schema compiler. It reads external * representations of schemas and prepares them for validation. * * <p> * The {@link SchemaFactory} class is not thread-safe. In other words, * it is the application's responsibility to ensure that at most * one thread is using a {@link SchemaFactory} object at any * given moment. Implementations are encouraged to mark methods * as {@code synchronized} to protect themselves from broken clients. * * <p> * {@link SchemaFactory} is not re-entrant. While one of the * {@code newSchema} methods is being invoked, applications * may not attempt to recursively invoke the {@code newSchema} method, * even from the same thread. * * <h2><a id="schemaLanguage"></a>Schema Language</h2> * <p> * This spec uses a namespace URI to designate a schema language. * The following table shows the values defined by this specification. * <p> * To be compliant with the spec, the implementation * is only required to support W3C XML Schema 1.0. However, * if it chooses to support other schema languages listed here, * it must conform to the relevant behaviors described in this spec. * * <p> * Schema languages not listed here are expected to * introduce their own URIs to represent themselves. * The {@link SchemaFactory} class is capable of locating other * implementations for other schema languages at run-time. * * <p> * Note that because the XML DTD is strongly tied to the parsing process * and has a significant effect on the parsing process, it is impossible * to define the DTD validation as a process independent from parsing. * For this reason, this specification does not define the semantics for * the XML DTD. This doesn't prohibit implementors from implementing it * in a way they see fit, but <em>users are warned that any DTD * validation implemented on this interface necessarily deviate from * the XML DTD semantics as defined in the XML 1.0</em>. * * <table class="striped"> * <caption>URIs for Supported Schema languages</caption> * <thead> * <tr> * <th scope="col">value</th> * <th scope="col">language</th> * </tr> * </thead> * <tbody> * <tr> * <th scope="row">{@link javax.xml.XMLConstants#W3C_XML_SCHEMA_NS_URI} ("{@code http://www.w3.org/2001/XMLSchema}")</th> * <td><a href="http://www.w3.org/TR/xmlschema-1">W3C XML Schema 1.0</a></td> * </tr> * <tr> * <th scope="row">{@link javax.xml.XMLConstants#RELAXNG_NS_URI} ("{@code http://relaxng.org/ns/structure/1.0}")</th> * <td><a href="http://www.relaxng.org/">RELAX NG 1.0</a></td> * </tr> * </tbody> * </table> * * @author Kohsuke Kawaguchi * @author Neeraj Bajaj * * @since 1.5 */ public abstract class SchemaFactory { /** * Constructor for derived classes. * * <p>The constructor does nothing. * * <p>Derived classes must create {@link SchemaFactory} objects that have * {@code null} {@link ErrorHandler} and * {@code null} {@link LSResourceResolver}. */ protected SchemaFactory() { } /** * Creates a new instance of the {@code SchemaFactory} builtin * system-default implementation. * * @implSpec The {@code SchemaFactory} builtin * system-default implementation is only required to support the * <a href="http://www.w3.org/TR/xmlschema-1">W3C XML Schema 1.0</a>, * but may support additional <a href="#schemaLanguage">schema languages</a>. * * @return A new instance of the {@code SchemaFactory} builtin * system-default implementation. * * @since 9 */ public static SchemaFactory newDefaultInstance() { return new XMLSchemaFactory(); } /** * Lookup an implementation of the {@code SchemaFactory} that supports the specified * schema language and return it. * * <p>To find a {@code SchemaFactory} object for a given schema language, * this method looks the following places in the following order * where "the class loader" refers to the context class loader: * <ol> * <li> * <p> * If the system property * {@code "javax.xml.validation.SchemaFactory:<i>schemaLanguage</i>"} * is present (where <i>schemaLanguage</i> is the parameter * to this method), then its value is read * as a class name. The method will try to * create a new instance of this class by using the class loader, * and returns it if it is successfully created. * </li> * <li> * <p> * Use the configuration file "jaxp.properties". The file is in standard * {@link java.util.Properties} format and typically located in the * 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. * <br> * Each potential service provider is required to implement the method * {@link #isSchemaLanguageSupported(String schemaLanguage)}. * <br> * The first service provider found that supports the specified schema * language is returned. * <br> * In case of {@link java.util.ServiceConfigurationError} a * {@link SchemaFactoryConfigurationError} will be thrown. * </li> * <li> * <p> * Platform default {@code SchemaFactory} is located * in an implementation specific way. There must be a * {@linkplain #newDefaultInstance() platform default} * {@code SchemaFactory} for W3C XML Schema. * </li> * </ol> * * <p>If everything fails, {@link IllegalArgumentException} will be thrown. * * <h4>Tip for Trouble-shooting:</h4> * <p>See {@link java.util.Properties#load(java.io.InputStream)} for * exactly how a property file is parsed. In particular, colons ':' * need to be escaped in a property file, so make sure schema language * URIs are properly escaped in it. For example: * <pre> * http\://www.w3.org/2001/XMLSchema=org.acme.foo.XSSchemaFactory * </pre> * * @param schemaLanguage * Specifies the schema language which the returned * SchemaFactory will understand. See * <a href="#schemaLanguage">the list of available * schema languages</a> for the possible values. * * @return New instance of a {@code SchemaFactory} * * @throws IllegalArgumentException * If no implementation of the schema language is available. * @throws NullPointerException * If the {@code schemaLanguage} parameter is null. * @throws SchemaFactoryConfigurationError * If a configuration error is encountered. * * @see #newInstance(String schemaLanguage, String factoryClassName, ClassLoader classLoader) */ public static SchemaFactory newInstance(String schemaLanguage) { ClassLoader cl; cl = SecuritySupport.getContextClassLoader(); if (cl == null) { //cl = ClassLoader.getSystemClassLoader(); //use the current class loader cl = SchemaFactory.class.getClassLoader(); } SchemaFactory f = new SchemaFactoryFinder(cl).newFactory(schemaLanguage); if (f == null) { throw new IllegalArgumentException("No SchemaFactory" + " that implements the schema language specified by: " + schemaLanguage + " could be loaded"); } return f; } /** * Obtain a new instance of a {@code SchemaFactory} from class name. {@code SchemaFactory} * is returned if specified factory class name supports the specified schema language. * 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. * * <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 schemaLanguage Specifies the schema language which the returned * {@code SchemaFactory} will understand. See * <a href="#schemaLanguage">the list of available * schema languages</a> for the possible values. * * @param factoryClassName fully qualified factory class name that provides implementation of {@code javax.xml.validation.SchemaFactory}. * * @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 SchemaFactory} * * @throws IllegalArgumentException * if {@code factoryClassName} is {@code null}, or * the factory class cannot be loaded, instantiated or doesn't * support the schema language specified in {@code schemLanguage} * parameter. * * @throws NullPointerException * If the {@code schemaLanguage} parameter is null. * * @see #newInstance(String schemaLanguage) * * @since 1.6 */ public static SchemaFactory newInstance(String schemaLanguage, String factoryClassName, ClassLoader classLoader) { ClassLoader cl = classLoader; if (cl == null) { cl = SecuritySupport.getContextClassLoader(); } SchemaFactory f = new SchemaFactoryFinder(cl).createInstance(factoryClassName); if (f == null) { throw new IllegalArgumentException("Factory " + factoryClassName + " could not be loaded to implement the schema language specified by: " + schemaLanguage); } //if this factory supports the given schemalanguage return this factory else thrown exception if (f.isSchemaLanguageSupported(schemaLanguage)) { return f; } else { throw new IllegalArgumentException("Factory " + f.getClass().getName() + " does not implement the schema language specified by: " + schemaLanguage); } } /** * Is specified schema supported by this {@code SchemaFactory}? * * @param schemaLanguage Specifies the schema language which the returned {@code SchemaFactory} will understand. * {@code schemaLanguage} must specify a <a href="#schemaLanguage">valid</a> schema language. * * @return {@code true} if {@code SchemaFactory} supports {@code schemaLanguage}, else {@code false}. * * @throws NullPointerException If {@code schemaLanguage} is {@code null}. * @throws IllegalArgumentException If {@code schemaLanguage.length() == 0} * or {@code schemaLanguage} does not specify a <a href="#schemaLanguage">valid</a> schema language. */ public abstract boolean isSchemaLanguageSupported(String schemaLanguage); /** * Look up the value of a feature flag. * * <p>The feature name is any fully-qualified URI. It is * possible for a {@link SchemaFactory} to recognize a feature name but * temporarily be unable to return its value. * * <p>Implementors are free (and encouraged) to invent their own features, * using names built on their own URIs. * * @param name The feature name, which is a non-null fully-qualified URI. * * @return The current value of the feature (true or false). * * @throws SAXNotRecognizedException If the feature * value can't be assigned or retrieved. * @throws SAXNotSupportedException When the * {@link SchemaFactory} recognizes the feature name but * cannot determine its value at this time. * @throws NullPointerException If {@code name} is {@code null}. * * @see #setFeature(String, boolean) */ public boolean getFeature(String name) throws SAXNotRecognizedException, SAXNotSupportedException { if (name == null) { throw new NullPointerException("the name parameter is null"); } throw new SAXNotRecognizedException(name); } /** * Set a feature for this {@code SchemaFactory}, * {@link Schema}s created by this factory, and by extension, * {@link Validator}s and {@link ValidatorHandler}s created by * those {@link Schema}s. * * <p>Implementors and developers should pay particular attention * to how the special {@link Schema} object returned by {@link * #newSchema()} is processed. In some cases, for example, when the * {@code SchemaFactory} and the class actually loading the * schema come from different implementations, it may not be possible * for {@code SchemaFactory} features to be inherited automatically. * Developers should * make sure that features, such as secure processing, are explicitly * set in both places. * * <p>The feature name is any fully-qualified URI. It is * possible for a {@link SchemaFactory} to expose a feature value but * to be unable to change the current value. * * <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 ErrorHandler#fatalError(SAXParseException exception)}. * See {@link #setErrorHandler(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 The feature name, which is a non-null fully-qualified URI. * @param value The requested value of the feature (true or false). * * @throws SAXNotRecognizedException If the feature * value can't be assigned or retrieved. * @throws SAXNotSupportedException When the * {@link SchemaFactory} recognizes the feature name but * cannot set the requested value. * @throws NullPointerException If {@code name} is {@code null}. * * @see #getFeature(String) */ public void setFeature(String name, boolean value) throws SAXNotRecognizedException, SAXNotSupportedException { if (name == null) { throw new NullPointerException("the name parameter is null"); } throw new SAXNotRecognizedException(name); } /** * Set the value of a property. * * <p>The property name is any fully-qualified URI. It is * possible for a {@link SchemaFactory} to recognize a property name but * to be unable to change the current value. * * <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> * <p>Access to external DTDs in Schema files is restricted to the protocols * specified by the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property. * If access is denied during the creation of new Schema due to the restriction * of this property, {@link org.xml.sax.SAXException} will be thrown by the * {@link #newSchema(Source)} or {@link #newSchema(File)} * or {@link #newSchema(URL)} or {@link #newSchema(Source[])} method. * * <p>Access to external DTDs in xml source files is restricted to the protocols * specified by the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property. * If access is denied during validation due to the restriction * of this property, {@link org.xml.sax.SAXException} will be thrown by the * {@link javax.xml.validation.Validator#validate(Source)} or * {@link javax.xml.validation.Validator#validate(Source, Result)} method. * * <p>Access to external reference set by the schemaLocation attribute is * restricted to the protocols specified by the * {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} property. * If access is denied during validation due to the restriction of this property, * {@link org.xml.sax.SAXException} will be thrown by the * {@link javax.xml.validation.Validator#validate(Source)} or * {@link javax.xml.validation.Validator#validate(Source, Result)} method. * * <p>Access to external reference set by the Import * and Include element is restricted to the protocols specified by the * {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} property. * If access is denied during the creation of new Schema due to the restriction * of this property, {@link org.xml.sax.SAXException} will be thrown by the * {@link #newSchema(Source)} or {@link #newSchema(File)} * or {@link #newSchema(URL)} or {@link #newSchema(Source[])} method. * </li> * </ul> * * @param name The property name, which is a non-null fully-qualified URI. * @param object The requested value for the property. * * @throws SAXNotRecognizedException If the property * value can't be assigned or retrieved. * @throws SAXNotSupportedException When the * {@link SchemaFactory} recognizes the property name but * cannot set the requested value. * @throws NullPointerException If {@code name} is {@code null}. */ public void setProperty(String name, Object object) throws SAXNotRecognizedException, SAXNotSupportedException { if (name == null) { throw new NullPointerException("the name parameter is null"); } throw new SAXNotRecognizedException(name); } /** * Look up the value of a property. * * <p>The property name is any fully-qualified URI. It is * possible for a {@link SchemaFactory} to recognize a property name but * temporarily be unable to return its value. * * <p>{@link SchemaFactory}s are not required to recognize any specific * property names. * * <p>Implementors are free (and encouraged) to invent their own properties, * using names built on their own URIs. * * @param name The property name, which is a non-null fully-qualified URI. * * @return The current value of the property. * * @throws SAXNotRecognizedException If the property * value can't be assigned or retrieved. * @throws SAXNotSupportedException When the * XMLReader recognizes the property name but * cannot determine its value at this time. * @throws NullPointerException If {@code name} is {@code null}. * * @see #setProperty(String, Object) */ public Object getProperty(String name) throws SAXNotRecognizedException, SAXNotSupportedException { if (name == null) { throw new NullPointerException("the name parameter is null"); } throw new SAXNotRecognizedException(name); } /** * Sets the {@link ErrorHandler} to receive errors encountered * during the {@code newSchema} method invocation. * * <p> * Error handler can be used to customize the error handling process * during schema parsing. When an {@link ErrorHandler} is set, * errors found during the parsing of schemas will be first sent * to the {@link ErrorHandler}. * * <p> * The error handler can abort the parsing of a schema immediately * by throwing {@link SAXException} from the handler. Or for example * it can print an error to the screen and try to continue the * processing by returning normally from the {@link ErrorHandler} * * <p> * If any {@link Throwable} (or instances of its derived classes) * is thrown from an {@link ErrorHandler}, * the caller of the {@code newSchema} method will be thrown * the same {@link Throwable} object. * * <p> * {@link SchemaFactory} is not allowed to * throw {@link SAXException} without first reporting it to * {@link ErrorHandler}. * * <p> * Applications can call this method even during a {@link Schema} * is being parsed. * * <p> * When the {@link ErrorHandler} is null, the implementation will * behave as if the following {@link ErrorHandler} is set: * <pre> * class DraconianErrorHandler implements {@link ErrorHandler} { * public void fatalError( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} { * throw e; * } * public void error( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} { * throw e; * } * public void warning( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} { * // noop * } * } * </pre> * * <p> * When a new {@link SchemaFactory} object is created, initially * this field is set to null. This field will <em>NOT</em> be * inherited to {@link Schema}s, {@link Validator}s, or * {@link ValidatorHandler}s that are created from this {@link SchemaFactory}. * * @param errorHandler A new error handler to be set. * This parameter can be {@code null}. */ public abstract void setErrorHandler(ErrorHandler errorHandler); /** * Gets the current {@link ErrorHandler} set to this {@link SchemaFactory}. * * @return * This method returns the object that was last set through * the {@link #setErrorHandler(ErrorHandler)} method, or null * if that method has never been called since this {@link SchemaFactory} * has created. * * @see #setErrorHandler(ErrorHandler) */ public abstract ErrorHandler getErrorHandler(); /** * Sets the {@link LSResourceResolver} to customize * resource resolution when parsing schemas. * * <p> * {@link SchemaFactory} uses a {@link LSResourceResolver} * when it needs to locate external resources while parsing schemas, * although exactly what constitutes "locating external resources" is * up to each schema language. For example, for W3C XML Schema, * this includes files {@code <include>}d or {@code <import>}ed, * and DTD referenced from schema files, etc. * * <p> * Applications can call this method even during a {@link Schema} * is being parsed. * * <p> * When the {@link LSResourceResolver} is null, the implementation will * behave as if the following {@link LSResourceResolver} is set: * <pre> * class DumbDOMResourceResolver implements {@link LSResourceResolver} { * public {@link org.w3c.dom.ls.LSInput} resolveResource( * String publicId, String systemId, String baseURI) { * * return null; // always return null * } * } * </pre> * * <p> * If a {@link LSResourceResolver} throws a {@link RuntimeException} * (or instances of its derived classes), * then the {@link SchemaFactory} will abort the parsing and * the caller of the {@code newSchema} method will receive * the same {@link RuntimeException}. * * <p> * When a new {@link SchemaFactory} object is created, initially * this field is set to null. This field will <em>NOT</em> be * inherited to {@link Schema}s, {@link Validator}s, or * {@link ValidatorHandler}s that are created from this {@link SchemaFactory}. * * @param resourceResolver * A new resource resolver to be set. This parameter can be null. */ public abstract void setResourceResolver(LSResourceResolver resourceResolver); /** * Gets the current {@link LSResourceResolver} set to this {@link SchemaFactory}. * * @return * This method returns the object that was last set through * the {@link #setResourceResolver(LSResourceResolver)} method, or null * if that method has never been called since this {@link SchemaFactory} * has created. * * @see #setErrorHandler(ErrorHandler) */ public abstract LSResourceResolver getResourceResolver(); /** * Parses the specified source as a schema and returns it as a schema. * * <p>This is a convenience method for {@link #newSchema(Source[] schemas)}. * * @param schema Source that represents a schema. * * @return New {@code Schema} from parsing {@code schema}. * * @throws SAXException If a SAX error occurs during parsing. * @throws NullPointerException if {@code schema} is null. */ public Schema newSchema(Source schema) throws SAXException { return newSchema(new Source[] { schema }); } /** * Parses the specified {@code File} as a schema and returns it as a {@code Schema}. * * <p>This is a convenience method for {@link #newSchema(Source schema)}. * * @param schema File that represents a schema. * * @return New {@code Schema} from parsing {@code schema}. * * @throws SAXException If a SAX error occurs during parsing. * @throws NullPointerException if {@code schema} is null. */ public Schema newSchema(File schema) throws SAXException { return newSchema(new StreamSource(schema)); } /** * Parses the specified {@code URL} as a schema and returns it as a {@code Schema}. * * <p>This is a convenience method for {@link #newSchema(Source schema)}. * * @param schema {@code URL} that represents a schema. * * @return New {@code Schema} from parsing {@code schema}. * * @throws SAXException If a SAX error occurs during parsing. * @throws NullPointerException if {@code schema} is null. */ public Schema newSchema(URL schema) throws SAXException { return newSchema(new StreamSource(schema.toExternalForm())); } /** * Parses the specified source(s) as a schema and returns it as a schema. * * <p> * The callee will read all the {@link Source}s and combine them into a * single schema. The exact semantics of the combination depends on the schema * language that this {@link SchemaFactory} object is created for. * * <p> * When an {@link ErrorHandler} is set, the callee will report all the errors * found in sources to the handler. If the handler throws an exception, it will * abort the schema compilation and the same exception will be thrown from * this method. Also, after an error is reported to a handler, the callee is allowed * to abort the further processing by throwing it. If an error handler is not set, * the callee will throw the first error it finds in the sources. * * <h4>W3C XML Schema 1.0</h4> * <p> * The resulting schema contains components from the specified sources. * The same result would be achieved if all these sources were * imported, using appropriate values for schemaLocation and namespace, * into a single schema document with a different targetNamespace * and no components of its own, if the import elements were given * in the same order as the sources. Section 4.2.3 of the XML Schema * recommendation describes the options processors have in this * regard. While a processor should be consistent in its treatment of * JAXP schema sources and XML Schema imports, the behaviour between * JAXP-compliant parsers may vary; in particular, parsers may choose * to ignore all but the first {@code <import>} for a given namespace, * regardless of information provided in schemaLocation. * * <p> * If the parsed set of schemas includes error(s) as * specified in the section 5.1 of the XML Schema spec, then * the error must be reported to the {@link ErrorHandler}. * * <h4>RELAX NG</h4> * * <p>For RELAX NG, this method must throw {@link UnsupportedOperationException} * if {@code schemas.length!=1}. * * * @param schemas * inputs to be parsed. {@link SchemaFactory} is required * to recognize {@link javax.xml.transform.sax.SAXSource}, * {@link StreamSource}, * {@link javax.xml.transform.stax.StAXSource}, * and {@link javax.xml.transform.dom.DOMSource}. * Input schemas must be XML documents or * XML elements and must not be null. For backwards compatibility, * the results of passing anything other than * a document or element are implementation-dependent. * Implementations must either recognize and process the input * or thrown an IllegalArgumentException. * * @return * Always return a non-null valid {@link Schema} object. * Note that when an error has been reported, there is no * guarantee that the returned {@link Schema} object is * meaningful. * * @throws SAXException * If an error is found during processing the specified inputs. * When an {@link ErrorHandler} is set, errors are reported to * there first. See {@link #setErrorHandler(ErrorHandler)}. * @throws NullPointerException * If the {@code schemas} parameter itself is null or * any item in the array is null. * @throws IllegalArgumentException * If any item in the array is not recognized by this method. * @throws UnsupportedOperationException * If the schema language doesn't support this operation. */ public abstract Schema newSchema(Source[] schemas) throws SAXException; /** * Creates a special {@link Schema} object. * * <p>The exact semantics of the returned {@link Schema} object * depend on the schema language for which this {@link SchemaFactory} * is created. * * <p>Also, implementations are allowed to use implementation-specific * property/feature to alter the semantics of this method. * * <p>Implementors and developers should pay particular attention * to how the features set on this {@link SchemaFactory} are * processed by this special {@link Schema}. * In some cases, for example, when the * {@link SchemaFactory} and the class actually loading the * schema come from different implementations, it may not be possible * for {@link SchemaFactory} features to be inherited automatically. * Developers should * make sure that features, such as secure processing, are explicitly * set in both places. * * <h4>W3C XML Schema 1.0</h4> * <p> * For XML Schema, this method creates a {@link Schema} object that * performs validation by using location hints specified in documents. * * <p> * The returned {@link Schema} object assumes that if documents * refer to the same URL in the schema location hints, * they will always resolve to the same schema document. This * asusmption allows implementations to reuse parsed results of * schema documents so that multiple validations against the same * schema will run faster. * * <p> * Note that the use of schema location hints introduces a * vulnerability to denial-of-service attacks. * * * <h4>RELAX NG</h4> * <p> * RELAX NG does not support this operation. * * @return * Always return non-null valid {@link Schema} object. * * @throws UnsupportedOperationException * If this operation is not supported by the callee. * @throws SAXException * If this operation is supported but failed for some reason. */ public abstract Schema newSchema() throws SAXException; }