1.初始化过程
1 Resource res = new ClassPathResource("/applicationContext.xml"); 2 XmlBeanFactory factory = new XmlBeanFactory(res);
2.入门
1 /** 2 * Create a new XmlBeanFactory with the given input stream, 3 * which must be parsable using DOM. 4 * @param resource XML resource to load bean definitions from 5 * @param parentBeanFactory parent bean factory 6 * @throws BeansException in case of loading or parsing errors 7 */ 8 public XmlBeanFactory(Resource resource, BeanFactory parentBeanFactory) throws BeansException { 9 super(parentBeanFactory); 10 this.reader.loadBeanDefinitions(resource); 11 }
3.读取配置文件XmlBeanDefinitionReader.java
1 public int loadBeanDefinitions(EncodedResource encodedResource) throws BeanDefinitionStoreException { 2 Assert.notNull(encodedResource, "EncodedResource must not be null"); 3 if (logger.isInfoEnabled()) { 4 logger.info("Loading XML bean definitions from " + encodedResource.getResource()); 5 } 6 7 Set currentResources = (Set) this.resourcesCurrentlyBeingLoaded.get(); 8 if (currentResources == null) { 9 currentResources = new HashSet(4); 10 this.resourcesCurrentlyBeingLoaded.set(currentResources); 11 } 12 if (!currentResources.add(encodedResource)) { 13 throw new BeanDefinitionStoreException( 14 "Detected recursive loading of " + encodedResource + " - check your import definitions!"); 15 } 16 try { 17 InputStream inputStream = encodedResource.getResource().getInputStream(); 18 try { 19 InputSource inputSource = new InputSource(inputStream); 20 if (encodedResource.getEncoding() != null) { 21 inputSource.setEncoding(encodedResource.getEncoding()); 22 } 23 return doLoadBeanDefinitions(inputSource, encodedResource.getResource()); 24 } 25 finally { 26 inputStream.close(); 27 } 28 } 29 catch (IOException ex) { 30 throw new BeanDefinitionStoreException( 31 "IOException parsing XML document from " + encodedResource.getResource(), ex); 32 } 33 finally { 34 currentResources.remove(encodedResource); 35 if (currentResources.isEmpty()) { 36 this.resourcesCurrentlyBeingLoaded.set(null); 37 } 38 } 39 }
4.读取方法DefaultBeanDefinitionDocumentReader.java
1 /** 2 * Parses bean definitions according to the "spring-beans" DTD. 3 * <p>Opens a DOM Document; then initializes the default settings 4 * specified at <code><beans></code> level; then parses 5 * the contained bean definitions. 6 */ 7 public void registerBeanDefinitions(Document doc, XmlReaderContext readerContext) { 8 this.readerContext = readerContext; 9 10 logger.debug("Loading bean definitions"); 11 Element root = doc.getDocumentElement(); 12 13 BeanDefinitionParserDelegate delegate = createHelper(readerContext, root); 14 15 preProcessXml(root); 16 parseBeanDefinitions(root, delegate); 17 postProcessXml(root); 18 }
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