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/* * Copyright 2002-2018 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.beans.factory.xml; import java.io.IOException; import java.io.InputStream; import java.util.HashSet; import java.util.Set; import javax.xml.parsers.ParserConfigurationException; import org.w3c.dom.Document; import org.xml.sax.EntityResolver; import org.xml.sax.ErrorHandler; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; import org.springframework.beans.BeanUtils; import org.springframework.beans.factory.BeanDefinitionStoreException; import org.springframework.beans.factory.parsing.EmptyReaderEventListener; import org.springframework.beans.factory.parsing.FailFastProblemReporter; import org.springframework.beans.factory.parsing.NullSourceExtractor; import org.springframework.beans.factory.parsing.ProblemReporter; import org.springframework.beans.factory.parsing.ReaderEventListener; import org.springframework.beans.factory.parsing.SourceExtractor; import org.springframework.beans.factory.support.AbstractBeanDefinitionReader; import org.springframework.beans.factory.support.BeanDefinitionRegistry; import org.springframework.core.Constants; import org.springframework.core.NamedThreadLocal; import org.springframework.core.io.DescriptiveResource; import org.springframework.core.io.Resource; import org.springframework.core.io.ResourceLoader; import org.springframework.core.io.support.EncodedResource; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.xml.SimpleSaxErrorHandler; import org.springframework.util.xml.XmlValidationModeDetector; /** * Bean definition reader for XML bean definitions. * Delegates the actual XML document reading to an implementation * of the {@link BeanDefinitionDocumentReader} interface. * * <p>Typically applied to a * {@link org.springframework.beans.factory.support.DefaultListableBeanFactory} * or a {@link org.springframework.context.support.GenericApplicationContext}. * * <p>This class loads a DOM document and applies the BeanDefinitionDocumentReader to it. * The document reader will register each bean definition with the given bean factory, * talking to the latter's implementation of the * {@link org.springframework.beans.factory.support.BeanDefinitionRegistry} interface. * * @author Juergen Hoeller * @author Rob Harrop * @author Chris Beams * @since 26.11.2003 * @see #setDocumentReaderClass * @see BeanDefinitionDocumentReader * @see DefaultBeanDefinitionDocumentReader * @see BeanDefinitionRegistry * @see org.springframework.beans.factory.support.DefaultListableBeanFactory * @see org.springframework.context.support.GenericApplicationContext */ public class XmlBeanDefinitionReader extends AbstractBeanDefinitionReader { /** * Indicates that the validation should be disabled. */ public static final int VALIDATION_NONE = XmlValidationModeDetector.VALIDATION_NONE; /** * Indicates that the validation mode should be detected automatically. */ public static final int VALIDATION_AUTO = XmlValidationModeDetector.VALIDATION_AUTO; /** * Indicates that DTD validation should be used. */ public static final int VALIDATION_DTD = XmlValidationModeDetector.VALIDATION_DTD; /** * Indicates that XSD validation should be used. */ public static final int VALIDATION_XSD = XmlValidationModeDetector.VALIDATION_XSD; /** Constants instance for this class. */ private static final Constants constants = new Constants(XmlBeanDefinitionReader.class); private int validationMode = VALIDATION_AUTO; private boolean namespaceAware = false; private Class<? extends BeanDefinitionDocumentReader> documentReaderClass = DefaultBeanDefinitionDocumentReader.class; private ProblemReporter problemReporter = new FailFastProblemReporter(); private ReaderEventListener eventListener = new EmptyReaderEventListener(); private SourceExtractor sourceExtractor = new NullSourceExtractor(); @Nullable private NamespaceHandlerResolver namespaceHandlerResolver; private DocumentLoader documentLoader = new DefaultDocumentLoader(); @Nullable private EntityResolver entityResolver; private ErrorHandler errorHandler = new SimpleSaxErrorHandler(logger); private final XmlValidationModeDetector validationModeDetector = new XmlValidationModeDetector(); private final ThreadLocal<Set<EncodedResource>> resourcesCurrentlyBeingLoaded = new NamedThreadLocal<>( "XML bean definition resources currently being loaded"); /** * Create new XmlBeanDefinitionReader for the given bean factory. * @param registry the BeanFactory to load bean definitions into, * in the form of a BeanDefinitionRegistry */ public XmlBeanDefinitionReader(BeanDefinitionRegistry registry) { super(registry); } /** * Set whether to use XML validation. Default is {@code true}. * <p>This method switches namespace awareness on if validation is turned off, * in order to still process schema namespaces properly in such a scenario. * @see #setValidationMode * @see #setNamespaceAware */ public void setValidating(boolean validating) { this.validationMode = (validating ? VALIDATION_AUTO : VALIDATION_NONE); this.namespaceAware = !validating; } /** * Set the validation mode to use by name. Defaults to {@link #VALIDATION_AUTO}. * @see #setValidationMode */ public void setValidationModeName(String validationModeName) { setValidationMode(constants.asNumber(validationModeName).intValue()); } /** * Set the validation mode to use. Defaults to {@link #VALIDATION_AUTO}. * <p>Note that this only activates or deactivates validation itself. * If you are switching validation off for schema files, you might need to * activate schema namespace support explicitly: see {@link #setNamespaceAware}. */ public void setValidationMode(int validationMode) { this.validationMode = validationMode; } /** * Return the validation mode to use. */ public int getValidationMode() { return this.validationMode; } /** * Set whether or not the XML parser should be XML namespace aware. * Default is "false". * <p>This is typically not needed when schema validation is active. * However, without validation, this has to be switched to "true" * in order to properly process schema namespaces. */ public void setNamespaceAware(boolean namespaceAware) { this.namespaceAware = namespaceAware; } /** * Return whether or not the XML parser should be XML namespace aware. */ public boolean isNamespaceAware() { return this.namespaceAware; } /** * Specify which {@link org.springframework.beans.factory.parsing.ProblemReporter} to use. * <p>The default implementation is {@link org.springframework.beans.factory.parsing.FailFastProblemReporter} * which exhibits fail fast behaviour. External tools can provide an alternative implementation * that collates errors and warnings for display in the tool UI. */ public void setProblemReporter(@Nullable ProblemReporter problemReporter) { this.problemReporter = (problemReporter != null ? problemReporter : new FailFastProblemReporter()); } /** * Specify which {@link ReaderEventListener} to use. * <p>The default implementation is EmptyReaderEventListener which discards every event notification. * External tools can provide an alternative implementation to monitor the components being * registered in the BeanFactory. */ public void setEventListener(@Nullable ReaderEventListener eventListener) { this.eventListener = (eventListener != null ? eventListener : new EmptyReaderEventListener()); } /** * Specify the {@link SourceExtractor} to use. * <p>The default implementation is {@link NullSourceExtractor} which simply returns {@code null} * as the source object. This means that - during normal runtime execution - * no additional source metadata is attached to the bean configuration metadata. */ public void setSourceExtractor(@Nullable SourceExtractor sourceExtractor) { this.sourceExtractor = (sourceExtractor != null ? sourceExtractor : new NullSourceExtractor()); } /** * Specify the {@link NamespaceHandlerResolver} to use. * <p>If none is specified, a default instance will be created through * {@link #createDefaultNamespaceHandlerResolver()}. */ public void setNamespaceHandlerResolver(@Nullable NamespaceHandlerResolver namespaceHandlerResolver) { this.namespaceHandlerResolver = namespaceHandlerResolver; } /** * Specify the {@link DocumentLoader} to use. * <p>The default implementation is {@link DefaultDocumentLoader} * which loads {@link Document} instances using JAXP. */ public void setDocumentLoader(@Nullable DocumentLoader documentLoader) { this.documentLoader = (documentLoader != null ? documentLoader : new DefaultDocumentLoader()); } /** * Set a SAX entity resolver to be used for parsing. * <p>By default, {@link ResourceEntityResolver} will be used. Can be overridden * for custom entity resolution, for example relative to some specific base path. */ public void setEntityResolver(@Nullable EntityResolver entityResolver) { this.entityResolver = entityResolver; } /** * Return the EntityResolver to use, building a default resolver * if none specified. */ protected EntityResolver getEntityResolver() { if (this.entityResolver == null) { // Determine default EntityResolver to use. ResourceLoader resourceLoader = getResourceLoader(); if (resourceLoader != null) { this.entityResolver = new ResourceEntityResolver(resourceLoader); } else { this.entityResolver = new DelegatingEntityResolver(getBeanClassLoader()); } } return this.entityResolver; } /** * Set an implementation of the {@code org.xml.sax.ErrorHandler} * interface for custom handling of XML parsing errors and warnings. * <p>If not set, a default SimpleSaxErrorHandler is used that simply * logs warnings using the logger instance of the view class, * and rethrows errors to discontinue the XML transformation. * @see SimpleSaxErrorHandler */ public void setErrorHandler(ErrorHandler errorHandler) { this.errorHandler = errorHandler; } /** * Specify the {@link BeanDefinitionDocumentReader} implementation to use, * responsible for the actual reading of the XML bean definition document. * <p>The default is {@link DefaultBeanDefinitionDocumentReader}. * @param documentReaderClass the desired BeanDefinitionDocumentReader implementation class */ public void setDocumentReaderClass(Class<? extends BeanDefinitionDocumentReader> documentReaderClass) { this.documentReaderClass = documentReaderClass; } /** * Load bean definitions from the specified XML file. * @param resource the resource descriptor for the XML file * @return the number of bean definitions found * @throws BeanDefinitionStoreException in case of loading or parsing errors */ @Override public int loadBeanDefinitions(Resource resource) throws BeanDefinitionStoreException { return loadBeanDefinitions(new EncodedResource(resource)); } /** * Load bean definitions from the specified XML file. * @param encodedResource the resource descriptor for the XML file, * allowing to specify an encoding to use for parsing the file * @return the number of bean definitions found * @throws BeanDefinitionStoreException in case of loading or parsing errors */ public int loadBeanDefinitions(EncodedResource encodedResource) throws BeanDefinitionStoreException { Assert.notNull(encodedResource, "EncodedResource must not be null"); if (logger.isTraceEnabled()) { logger.trace("Loading XML bean definitions from " + encodedResource); } Set<EncodedResource> currentResources = this.resourcesCurrentlyBeingLoaded.get(); if (currentResources == null) { currentResources = new HashSet<>(4); this.resourcesCurrentlyBeingLoaded.set(currentResources); } if (!currentResources.add(encodedResource)) { throw new BeanDefinitionStoreException( "Detected cyclic loading of " + encodedResource + " - check your import definitions!"); } try { InputStream inputStream = encodedResource.getResource().getInputStream(); try { InputSource inputSource = new InputSource(inputStream); if (encodedResource.getEncoding() != null) { inputSource.setEncoding(encodedResource.getEncoding()); } return doLoadBeanDefinitions(inputSource, encodedResource.getResource()); } finally { inputStream.close(); } } catch (IOException ex) { throw new BeanDefinitionStoreException( "IOException parsing XML document from " + encodedResource.getResource(), ex); } finally { currentResources.remove(encodedResource); if (currentResources.isEmpty()) { this.resourcesCurrentlyBeingLoaded.remove(); } } } /** * Load bean definitions from the specified XML file. * @param inputSource the SAX InputSource to read from * @return the number of bean definitions found * @throws BeanDefinitionStoreException in case of loading or parsing errors */ public int loadBeanDefinitions(InputSource inputSource) throws BeanDefinitionStoreException { return loadBeanDefinitions(inputSource, "resource loaded through SAX InputSource"); } /** * Load bean definitions from the specified XML file. * @param inputSource the SAX InputSource to read from * @param resourceDescription a description of the resource * (can be {@code null} or empty) * @return the number of bean definitions found * @throws BeanDefinitionStoreException in case of loading or parsing errors */ public int loadBeanDefinitions(InputSource inputSource, @Nullable String resourceDescription) throws BeanDefinitionStoreException { return doLoadBeanDefinitions(inputSource, new DescriptiveResource(resourceDescription)); } /** * Actually load bean definitions from the specified XML file. * @param inputSource the SAX InputSource to read from * @param resource the resource descriptor for the XML file * @return the number of bean definitions found * @throws BeanDefinitionStoreException in case of loading or parsing errors * @see #doLoadDocument * @see #registerBeanDefinitions */ protected int doLoadBeanDefinitions(InputSource inputSource, Resource resource) throws BeanDefinitionStoreException { try { Document doc = doLoadDocument(inputSource, resource); int count = registerBeanDefinitions(doc, resource); if (logger.isDebugEnabled()) { logger.debug("Loaded " + count + " bean definitions from " + resource); } return count; } catch (BeanDefinitionStoreException ex) { throw ex; } catch (SAXParseException ex) { throw new XmlBeanDefinitionStoreException(resource.getDescription(), "Line " + ex.getLineNumber() + " in XML document from " + resource + " is invalid", ex); } catch (SAXException ex) { throw new XmlBeanDefinitionStoreException(resource.getDescription(), "XML document from " + resource + " is invalid", ex); } catch (ParserConfigurationException ex) { throw new BeanDefinitionStoreException(resource.getDescription(), "Parser configuration exception parsing XML from " + resource, ex); } catch (IOException ex) { throw new BeanDefinitionStoreException(resource.getDescription(), "IOException parsing XML document from " + resource, ex); } catch (Throwable ex) { throw new BeanDefinitionStoreException(resource.getDescription(), "Unexpected exception parsing XML document from " + resource, ex); } } /** * Actually load the specified document using the configured DocumentLoader. * @param inputSource the SAX InputSource to read from * @param resource the resource descriptor for the XML file * @return the DOM Document * @throws Exception when thrown from the DocumentLoader * @see #setDocumentLoader * @see DocumentLoader#loadDocument */ protected Document doLoadDocument(InputSource inputSource, Resource resource) throws Exception { return this.documentLoader.loadDocument(inputSource, getEntityResolver(), this.errorHandler, getValidationModeForResource(resource), isNamespaceAware()); } /** * Determine the validation mode for the specified {@link Resource}. * If no explicit validation mode has been configured, then the validation * mode gets {@link #detectValidationMode detected} from the given resource. * <p>Override this method if you would like full control over the validation * mode, even when something other than {@link #VALIDATION_AUTO} was set. * @see #detectValidationMode */ protected int getValidationModeForResource(Resource resource) { int validationModeToUse = getValidationMode(); if (validationModeToUse != VALIDATION_AUTO) { return validationModeToUse; } int detectedMode = detectValidationMode(resource); if (detectedMode != VALIDATION_AUTO) { return detectedMode; } // Hmm, we didn't get a clear indication... Let's assume XSD, // since apparently no DTD declaration has been found up until // detection stopped (before finding the document's root tag). return VALIDATION_XSD; } /** * Detect which kind of validation to perform on the XML file identified * by the supplied {@link Resource}. If the file has a {@code DOCTYPE} * definition then DTD validation is used otherwise XSD validation is assumed. * <p>Override this method if you would like to customize resolution * of the {@link #VALIDATION_AUTO} mode. */ protected int detectValidationMode(Resource resource) { if (resource.isOpen()) { throw new BeanDefinitionStoreException("Passed-in Resource [" + resource + "] contains an open stream: " + "cannot determine validation mode automatically. Either pass in a Resource " + "that is able to create fresh streams, or explicitly specify the validationMode " + "on your XmlBeanDefinitionReader instance."); } InputStream inputStream; try { inputStream = resource.getInputStream(); } catch (IOException ex) { throw new BeanDefinitionStoreException( "Unable to determine validation mode for [" + resource + "]: cannot open InputStream. " + "Did you attempt to load directly from a SAX InputSource without specifying the " + "validationMode on your XmlBeanDefinitionReader instance?", ex); } try { return this.validationModeDetector.detectValidationMode(inputStream); } catch (IOException ex) { throw new BeanDefinitionStoreException("Unable to determine validation mode for [" + resource + "]: an error occurred whilst reading from the InputStream.", ex); } } /** * Register the bean definitions contained in the given DOM document. * Called by {@code loadBeanDefinitions}. * <p>Creates a new instance of the parser class and invokes * {@code registerBeanDefinitions} on it. * @param doc the DOM document * @param resource the resource descriptor (for context information) * @return the number of bean definitions found * @throws BeanDefinitionStoreException in case of parsing errors * @see #loadBeanDefinitions * @see #setDocumentReaderClass * @see BeanDefinitionDocumentReader#registerBeanDefinitions */ public int registerBeanDefinitions(Document doc, Resource resource) throws BeanDefinitionStoreException { BeanDefinitionDocumentReader documentReader = createBeanDefinitionDocumentReader(); int countBefore = getRegistry().getBeanDefinitionCount(); documentReader.registerBeanDefinitions(doc, createReaderContext(resource)); return getRegistry().getBeanDefinitionCount() - countBefore; } /** * Create the {@link BeanDefinitionDocumentReader} to use for actually * reading bean definitions from an XML document. * <p>The default implementation instantiates the specified "documentReaderClass". * @see #setDocumentReaderClass */ protected BeanDefinitionDocumentReader createBeanDefinitionDocumentReader() { return BeanUtils.instantiateClass(this.documentReaderClass); } /** * Create the {@link XmlReaderContext} to pass over to the document reader. */ public XmlReaderContext createReaderContext(Resource resource) { return new XmlReaderContext(resource, this.problemReporter, this.eventListener, this.sourceExtractor, this, getNamespaceHandlerResolver()); } /** * Lazily create a default NamespaceHandlerResolver, if not set before. * @see #createDefaultNamespaceHandlerResolver() */ public NamespaceHandlerResolver getNamespaceHandlerResolver() { if (this.namespaceHandlerResolver == null) { this.namespaceHandlerResolver = createDefaultNamespaceHandlerResolver(); } return this.namespaceHandlerResolver; } /** * Create the default implementation of {@link NamespaceHandlerResolver} used if none is specified. * <p>The default implementation returns an instance of {@link DefaultNamespaceHandlerResolver}. * @see DefaultNamespaceHandlerResolver#DefaultNamespaceHandlerResolver(ClassLoader) */ protected NamespaceHandlerResolver createDefaultNamespaceHandlerResolver() { ClassLoader cl = (getResourceLoader() != null ? getResourceLoader().getClassLoader() : getBeanClassLoader()); return new DefaultNamespaceHandlerResolver(cl); } }