官方承諾：K60至尊版將會(huì)首批升級(jí)MIUI 15
全新的MIUI 15今天也有了消息，在官宣了K60至尊版將會(huì)搭載天璣9200+處理器和獨(dú)顯芯片X7的同時(shí)，Redmi給出了官方承諾，K60至尊重大更新首批升級(jí)，會(huì)首批推送MIUI 15。也就是說雖然
加載過程： 通過 ResourceLoader和其子類DefaultResourceLoader完成資源文件位置定位，實(shí)現(xiàn)從類路徑，文件系統(tǒng)，url等方式定位功能，完成定位后得到Resource對(duì)象，再交給BeanDefinitionReader，它再委托給
BeanDefinitionParserDelegate完成bean的解析并得到BeanDefinition對(duì)象，然后通過registerBeanDefinition方法進(jìn)行注冊(cè)，IOC容器內(nèi)ibu維護(hù)了一個(gè)HashMap來保存該BeanDefinition對(duì)象，Spring中的BeanDefinition其實(shí)就是我們用的JavaBean。
BeanDefinition是一個(gè)接口，描述了一個(gè)bean實(shí)例，它具有屬性值，構(gòu)造函數(shù)參數(shù)值以及具體實(shí)現(xiàn)提供的更多信息。
在開始之前需要認(rèn)真閱讀和理解這個(gè)過程，有了這個(gè)過程，閱讀源碼難度就小了一半。
大多源碼都進(jìn)行了注釋，有的是官方英文注釋。
一個(gè)普通的bean配置文件，這里我要強(qiáng)調(diào)的是它里面的格式，因?yàn)榻馕鰳?biāo)簽的時(shí)候會(huì)用到。它有<beans>``<bean>``<import>``<alias>等標(biāo)簽，下文會(huì)對(duì)他們進(jìn)行解析并翻譯成BeanDefinition對(duì)象。
<beans> <!-- this definition could be inside one beanRefFactory.xml file --> <bean id="a.qualified.name.of.some.sort" class="org.springframework.context.support.ClassPathXmlApplicationContext"> <property name="configLocation" value="org/springframework/web/context/beans1.xml"/> </bean> <!-- while the following two could be inside another, also on the classpath, perhaps coming from another component jar --> <bean id="another.qualified.name" class="org.springframework.context.support.ClassPathXmlApplicationContext"> <property name="configLocation" value="org/springframework/web/context/beans1.xml"/> <property name="parent" ref="a.qualified.name.of.some.sort"/> </bean> <alias name="another.qualified.name" alias="a.qualified.name.which.is.an.alias"/></beans>加載資源的策略接口(策略模式)。
DefaultResourceLoader is a standalone implementation that is usable outside an ApplicationContext, also used by ResourceEditorAn ApplicationContext is required to provide this functionality, plus extended ResourcePatternResolver support.
public interface ResourceLoader { /** Pseudo URL prefix for loading from the class path: "classpath:". */ String CLASSPATH_URL_PREFIX = ResourceUtils.CLASSPATH_URL_PREFIX; // 返回一個(gè)Resource 對(duì)象 (明確配置文件位置的對(duì)象) Resource getResource(String location); // 返回ResourceLoader的ClassLoader @Nullable ClassLoader getClassLoader();}然后我們看看DefaultResourceLoader對(duì)于getResource()方法的實(shí)現(xiàn)。
public Resource getResource(String location) { Assert.notNull(location, "Location must not be null"); for (ProtocolResolver protocolResolver : this.protocolResolvers) { Resource resource = protocolResolver.resolve(location, this); if (resource != null) { return resource; } } // 如果location 以 / 開頭 if (location.startsWith("/")) { return getResourceByPath(location); } // 如果location 以classpath: 開頭 else if (location.startsWith(CLASSPATH_URL_PREFIX)) { return new ClassPathResource(location.substring(CLASSPATH_URL_PREFIX.length()), getClassLoader()); } else { try { // Try to parse the location as a URL... URL url = new URL(location); return (ResourceUtils.isFileURL(url) ? new FileUrlResource(url) : new UrlResource(url)); } catch (MalformedURLException ex) { // No URL -> resolve as resource path. return getResourceByPath(location); } } }可以看到，它判斷了三種情況：/ classpath: url格式匹配， 然后調(diào)用相對(duì)應(yīng)的處理方法，我只分析classpath:，因?yàn)檫@是最常用的。所以看一看ClassPathResource實(shí)現(xiàn)：
public ClassPathResource(String path, @Nullable ClassLoader classLoader) { Assert.notNull(path, "Path must not be null"); String pathToUse = StringUtils.cleanPath(path); if (pathToUse.startsWith("/")) { pathToUse = pathToUse.substring(1); } this.path = pathToUse; this.classLoader = (classLoader != null ? classLoader : ClassUtils.getDefaultClassLoader()); }看了上面的代碼，意味著你配置靜態(tài)資源文件路徑的時(shí)候，不用糾結(jié)classpath:后面用不用寫/,因?yàn)槿绻麑懥怂鼤?huì)給你過濾掉。
那url如何定位的呢?
跟蹤getResourceByPath(location)方法:
@Override protected Resource getResourceByPath(String path) { if (path.startsWith("/")) { path = path.substring(1); } // 這里使用文件系統(tǒng)資源對(duì)象來定義bean文件 return new FileSystemResource(path); }好了，很明顯…跑偏了，因?yàn)槲覀兿胍氖莤ml文件及路徑的解析，不過還好，換湯不換藥。下文中會(huì)涉及到。
回到正題，我們?cè)谑褂胹pring手動(dòng)加載bean.xml的時(shí)候，用到：
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("bean.xml");那就從ClassPathXmlApplicationContext開始：
這個(gè)類里面只有構(gòu)造方法(多個(gè))和一個(gè)getConfigResources()方法，構(gòu)造方法最終都統(tǒng)一打到下面這個(gè)構(gòu)造方法中(Spring源碼經(jīng)常這樣，適配器模式):
public ClassPathXmlApplicationContext( String[] configLocations, boolean refresh, @Nullable ApplicationContext parent) throws BeansException { // 動(dòng)態(tài)的確定用哪個(gè)加載器去加載 配置文件 1.super(parent); // 告訴讀取器 配置文件在哪里， 定位加載配置文件 2.setConfigLocations(configLocations); // 刷新 if (refresh) { // 在創(chuàng)建IOC容器前，如果容器已經(jīng)存在，則需要把已有的容器摧毀和關(guān)閉，以保證refresh //之后使用的是新的IOC容器 3.refresh(); } }注意: 這個(gè)類非常關(guān)鍵，我認(rèn)為它定義了一個(gè)xml加載bean的一個(gè)Life Cycle:
我標(biāo)記的1. 2. 3. 對(duì)應(yīng)后面的方法x, 方便閱讀。
先深入了解下setConfigLocations(configLocations);方法:
// 解析Bean定義資源文件的路徑，處理多個(gè)資源文件字符串?dāng)?shù)組 public void setConfigLocations(@Nullable String... locations) { if (locations != null) { Assert.noNullElements(locations, "Config locations must not be null"); this.configLocations = new String[locations.length]; for (int i = 0; i < locations.length; i++) { // resolvePath 為同一個(gè)類中將字符串解析為路徑的方法 this.configLocations[i] = resolvePath(locations[i]).trim(); } } else { this.configLocations = null; } }然后我們繼續(xù)上面看ClassPathXmlApplicationContext的refresh()方法:
public void refresh() throws BeansException, IllegalStateException { synchronized (this.startupShutdownMonitor) { // 為refresh 準(zhǔn)備上下文 prepareRefresh(); // 通知子類去刷新 Bean工廠 ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory(); // 用該 上下文來 準(zhǔn)備bean工廠 prepareBeanFactory(beanFactory); try { // Allows post-processing of the bean factory in context subclasses. postProcessBeanFactory(beanFactory); // Invoke factory processors registered as beans in the context. invokeBeanFactoryPostProcessors(beanFactory); // Register bean processors that intercept bean creation. registerBeanPostProcessors(beanFactory); // Initialize message source for this context. initMessageSource(); // Initialize event multicaster for this context. initApplicationEventMulticaster(); // Initialize other special beans in specific context subclasses. onRefresh(); // Check for listener beans and register them. registerListeners(); // Instantiate all remaining (non-lazy-init) singletons. finishBeanFactoryInitialization(beanFactory); // Last step: publish corresponding event. finishRefresh(); } catch (BeansException ex) { if (logger.isWarnEnabled()) { logger.warn("Exception encountered during context initialization - " + "cancelling refresh attempt: " + ex); } // Destroy already created singletons to avoid dangling resources. destroyBeans(); // Reset 'active' flag. cancelRefresh(ex); // Propagate exception to caller. throw ex; } finally { // Reset common introspection caches in Spring's core, since we // might not ever need metadata for singleton beans anymore... resetCommonCaches(); } } }**注:**下面的方法全都是圍繞refresh()里深入閱讀，該方法套的很深，下面的閱讀可能會(huì)引起不適。
然后看看refresh()方法中的obtainFreshBeanFactory()方法。
// 調(diào)用--刷新bean工廠 protected ConfigurableListableBeanFactory obtainFreshBeanFactory() { // 委派模式：父類定義了refreshBeanFactory方法，具體實(shí)現(xiàn)調(diào)用子類容器 refreshBeanFactory(); return getBeanFactory(); }然后看obtainFreshBeanFactory()的 refreshBeanFactory()方法。
// 刷新bean工廠 protected final void refreshBeanFactory() throws BeansException { // 如果存在容器，就先銷毀并關(guān)閉 if (hasBeanFactory()) { destroyBeans(); closeBeanFactory(); } try { // 創(chuàng)建IOC容器 DefaultListableBeanFactory beanFactory = createBeanFactory(); beanFactory.setSerializationId(getId()); // 對(duì)容器進(jìn)行初始化 customizeBeanFactory(beanFactory); // 調(diào)用載入Bean定義的方法，(使用了委派模式) loadBeanDefinitions(beanFactory); synchronized (this.beanFactoryMonitor) { this.beanFactory = beanFactory; } } catch (IOException ex) { throw new ApplicationContextException("I/O error parsing bean definition source for " + getDisplayName(), ex); } }然后再跟進(jìn)refreshBeanFactory() 的loadBeanDefinitions()方法。
通過 XmlBeanDefinitionReader 加載 BeanDefinition。
// 通過 XmlBeanDefinitionReader 加載 BeanDefinition @Override protected void loadBeanDefinitions(DefaultListableBeanFactory beanFactory) throws BeansException, IOException { // Create a new XmlBeanDefinitionReader for the given BeanFactory. // 為beanFactory 創(chuàng)建一個(gè)新的 XmlBeanDefinitionReader XmlBeanDefinitionReader beanDefinitionReader = new XmlBeanDefinitionReader(beanFactory); // Configure the bean definition reader with this context's // resource loading environment. beanDefinitionReader.setEnvironment(this.getEnvironment()); // 為 Bean讀取器設(shè)置Spring資源加載器 (因?yàn)樽娓割愂荝esourceLoader的子類，所以也是ResourceLoader) beanDefinitionReader.setResourceLoader(this); // 為 Bean讀取器設(shè)置SAX xml解析器DOM4J beanDefinitionReader.setEntityResolver(new ResourceEntityResolver(this)); // Allow a subclass to provide custom initialization of the reader, // then proceed with actually loading the bean definitions. // 初始化 BeanDefinition讀取器 initBeanDefinitionReader(beanDefinitionReader); // 真正加載 bean定義 loadBeanDefinitions(beanDefinitionReader); }再跟進(jìn)loadBeanDefinitions(DefaultListableBeanFactory beanFactory)方法中的loadBeanDefinitions(XmlBeanDefinitionReader reader)方法。
XMLBean讀取器加載BeanDefinition 資源。
// XMLBean讀取器加載Bean 定義資源 protected void loadBeanDefinitions(XmlBeanDefinitionReader reader) throws BeansException, IOException { // 獲取Bean定義資源的定位 Resource[] configResources = getConfigResources(); if (configResources != null) { // XMLBean讀取器調(diào)用其父類 AbstractBeanDefinitionReader 讀取定位的Bean定義資源 reader.loadBeanDefinitions(configResources); } // 如果子類中獲取的bean定義資源定位為空， // 則獲取 FileSystemXmlApplicationContext構(gòu)造方法中 setConfigLocations 方法設(shè)置的資源 String[] configLocations = getConfigLocations(); if (configLocations != null) { // XMLBean讀取器調(diào)用其父類 AbstractBeanDefinitionReader 讀取定位的Bean定義資源 reader.loadBeanDefinitions(configLocations); } }@Override public int loadBeanDefinitions(Resource... resources) throws BeanDefinitionStoreException { Assert.notNull(resources, "Resource array must not be null"); int count = 0; // for (Resource resource : resources) { count += loadBeanDefinitions(resource); } return count; }再跟下去loadBeanDefinitions(): 這只是一個(gè)抽象方法，找到XmlBeanDefinitionReader子類的實(shí)現(xiàn)：
@Override public int loadBeanDefinitions(Resource resource) throws BeanDefinitionStoreException { return loadBeanDefinitions(new EncodedResource(resource)); }再深入loadBeanDefinitions:
通過明確的xml文件加載bean
// 通過明確的xml文件加載bean 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 { // 將資源文件轉(zhuǎn)為InputStream的IO流 InputStream inputStream = encodedResource.getResource().getInputStream(); try { // 從流中獲取 xml解析資源 InputSource inputSource = new InputSource(inputStream); if (encodedResource.getEncoding() != null) { // 設(shè)置編碼 inputSource.setEncoding(encodedResource.getEncoding()); } // 具體的讀取過程 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(); } } }再深入到doLoadBeanDefinitions():
真正開始加載 BeanDefinitions。
protected int doLoadBeanDefinitions(InputSource inputSource, Resource resource) throws BeanDefinitionStoreException { try { // 將xml 文件轉(zhuǎn)換為DOM對(duì)象 Document doc = doLoadDocument(inputSource, resource); // 對(duì)bean定義解析的過程，該過程會(huì)用到 Spring的bean配置規(guī)則 int count = registerBeanDefinitions(doc, resource); if (logger.isDebugEnabled()) { logger.debug("Loaded " + count + " bean definitions from " + resource); } return count; } ... ... ..}doLoadDocument()方法將流進(jìn)行解析，返回一個(gè)Document對(duì)象:return builder.parse(inputSource);為了避免擾亂思路，這里的深入自己去完成。
還需要再深入到:registerBeanDefinitions()。
注冊(cè) BeanDefinitions。
public int registerBeanDefinitions(Document doc, Resource resource) throws BeanDefinitionStoreException { BeanDefinitionDocumentReader documentReader = createBeanDefinitionDocumentReader(); // 得到容器中注冊(cè)的bean數(shù)量 int countBefore = getRegistry().getBeanDefinitionCount(); // 解析過程入口，這里使用了委派模式 documentReader.registerBeanDefinitions(doc, createReaderContext(resource)); // 統(tǒng)計(jì)解析的bean數(shù)量 return getRegistry().getBeanDefinitionCount() - countBefore; }再深入registerBeanDefinitions()方法（該方法是委派模式的結(jié)果）:
@Override public void registerBeanDefinitions(Document doc, XmlReaderContext readerContext) { // 獲得XML描述符 this.readerContext = readerContext; doRegisterBeanDefinitions(doc.getDocumentElement()); }再深入doRegisterBeanDefinitions(doc.getDocumentElement());：
真正開始注冊(cè) BeanDefinitions :
protected void doRegisterBeanDefinitions(Element root) { // Any nested <beans> elements will cause recursion in this method. In // order to propagate and preserve <beans> default-* attributes correctly, // keep track of the current (parent) delegate, which may be null. Create // the new (child) delegate with a reference to the parent for fallback purposes, // then ultimately reset this.delegate back to its original (parent) reference. // this behavior emulates a stack of delegates without actually necessitating one. BeanDefinitionParserDelegate parent = this.delegate; this.delegate = createDelegate(getReaderContext(), root, parent); if (this.delegate.isDefaultNamespace(root)) { String profileSpec = root.getAttribute(PROFILE_ATTRIBUTE); if (StringUtils.hasText(profileSpec)) { String[] specifiedProfiles = StringUtils.tokenizeToStringArray( profileSpec, BeanDefinitionParserDelegate.MULTI_VALUE_ATTRIBUTE_DELIMITERS); // We cannot use Profiles.of(...) since profile expressions are not supported // in XML config. See SPR-12458 for details. if (!getReaderContext().getEnvironment().acceptsProfiles(specifiedProfiles)) { if (logger.isDebugEnabled()) { logger.debug("Skipped XML bean definition file due to specified profiles [" + profileSpec + "] not matching: " + getReaderContext().getResource()); } return; } } } // 在bean解析定義之前，進(jìn)行自定義解析，看是否是用戶自定義標(biāo)簽 preProcessXml(root); // 開始進(jìn)行解析bean定義的document對(duì)象 parseBeanDefinitions(root, this.delegate); // 解析bean定義之后，進(jìn)行自定義的解析，增加解析過程的可擴(kuò)展性 postProcessXml(root); this.delegate = parent; }接下來看parseBeanDefinitions(root, this.delegate)。
document的根元素開始進(jìn)行解析翻譯成BeanDefinitions。
// 從document的根元素開始進(jìn)行解析翻譯成BeanDefinitions protected void parseBeanDefinitions(Element root, BeanDefinitionParserDelegate delegate) { // bean定義的document對(duì)象使用了spring默認(rèn)的xml命名空間 if (delegate.isDefaultNamespace(root)) { // 獲取bean定義的document對(duì)象根元素的所有字節(jié)點(diǎn) NodeList nl = root.getChildNodes(); for (int i = 0; i < nl.getLength(); i++) { Node node = nl.item(i); // 獲得document節(jié)點(diǎn)是xml元素節(jié)點(diǎn) if (node instanceof Element) { Element ele = (Element) node; // bean定義的document的元素節(jié)點(diǎn)使用的是spring默認(rèn)的xml命名空間 if (delegate.isDefaultNamespace(ele)) { // 使用spring的bean規(guī)則解析元素 節(jié)點(diǎn) parseDefaultElement(ele, delegate); } else { // 沒有使用spring默認(rèn)的xml命名空間，則使用用戶自定義的解析規(guī)則解析元素節(jié)點(diǎn) delegate.parseCustomElement(ele); } } } } else { delegate.parseCustomElement(root); } } private void parseDefaultElement(Element ele, BeanDefinitionParserDelegate delegate) { // 解析 <import> 標(biāo)簽元素，并進(jìn)行導(dǎo)入解析 if (delegate.nodeNameEquals(ele, IMPORT_ELEMENT)) { importBeanDefinitionResource(ele); } // alias else if (delegate.nodeNameEquals(ele, ALIAS_ELEMENT)) { processAliasRegistration(ele); } // bean else if (delegate.nodeNameEquals(ele, BEAN_ELEMENT)) { processBeanDefinition(ele, delegate); } // beans else if (delegate.nodeNameEquals(ele, NESTED_BEANS_ELEMENT)) { // recurse doRegisterBeanDefinitions(ele); } }importBeanDefinitionResource(ele);``processAliasRegistration(ele);``processBeanDefinition(ele, delegate);這三個(gè)方法里分別展示了標(biāo)簽解析的詳細(xì)過程。
這下看到了，它其實(shí)使用DOM4J來解析import bean alias等標(biāo)簽，然后遞歸標(biāo)簽內(nèi)部直到拿到所有屬性并封裝到BeanDefition對(duì)象中。比如說processBeanDefinition方法。
給我一個(gè)element 解析成 BeanDefinition。
// 給我一個(gè)element 解析成 BeanDefinition protected void processBeanDefinition(Element ele, BeanDefinitionParserDelegate delegate) { // 真正解析過程 BeanDefinitionHolder bdHolder = delegate.parseBeanDefinitionElement(ele); if (bdHolder != null) { bdHolder = delegate.decorateBeanDefinitionIfRequired(ele, bdHolder); try { // Register the final decorated instance. // 注冊(cè)： 將db注冊(cè)到ioc，委托模式 BeanDefinitionReaderUtils.registerBeanDefinition(bdHolder, getReaderContext().getRegistry()); } catch (BeanDefinitionStoreException ex) { getReaderContext().error("Failed to register bean definition with name '" + bdHolder.getBeanName() + "'", ele, ex); } // Send registration event. getReaderContext().fireComponentRegistered(new BeanComponentDefinition(bdHolder)); } }繼續(xù)深入registerBeanDefinition()。
注冊(cè)BeanDefinitions 到 bean 工廠。
// 注冊(cè)BeanDefinitions 到 bean 工廠 // definitionHolder ： bean定義，包含了 name和aliases // registry： 注冊(cè)到的bean工廠 public static void registerBeanDefinition( BeanDefinitionHolder definitionHolder, BeanDefinitionRegistry registry) throws BeanDefinitionStoreException { // Register bean definition under primary name. String beanName = definitionHolder.getBeanName(); // 真正注冊(cè) registry.registerBeanDefinition(beanName, definitionHolder.getBeanDefinition()); // Register aliases for bean name, if any. String[] aliases = definitionHolder.getAliases(); if (aliases != null) { for (String alias : aliases) { registry.registerAlias(beanName, alias); } } }再深入registry.registerBeanDefinition(beanName, definitionHolder.getBeanDefinition())。
注冊(cè)BeanDefinitions 到IOC容器。
注意:該方法所在類是接口，我們查看的是DefaultListableBeanFactory.java所實(shí)現(xiàn)的該方法。
// 實(shí)現(xiàn)BeanDefinitionRegistry接口,注冊(cè)BeanDefinitions @Override public void registerBeanDefinition(String beanName, BeanDefinition beanDefinition) throws BeanDefinitionStoreException { Assert.hasText(beanName, "Bean name must not be empty"); Assert.notNull(beanDefinition, "BeanDefinition must not be null"); // 校驗(yàn)是否是 AbstractBeanDefinition) if (beanDefinition instanceof AbstractBeanDefinition) { try { // 標(biāo)記 beanDefinition 生效 ((AbstractBeanDefinition) beanDefinition).validate(); } catch (BeanDefinitionValidationException ex) { throw new BeanDefinitionStoreException(beanDefinition.getResourceDescription(), beanName, "Validation of bean definition failed", ex); } } // 判斷beanDefinitionMap 里是否已經(jīng)有這個(gè)bean BeanDefinition existingDefinition = this.beanDefinitionMap.get(beanName); //如果沒有這個(gè)bean if (existingDefinition != null) { //如果不允許bd 覆蓋已注冊(cè)的bean， 就拋出異常 if (!isAllowBeanDefinitionOverriding()) { throw new BeanDefinitionOverrideException(beanName, beanDefinition, existingDefinition); } // 如果允許覆蓋， 則同名的bean， 注冊(cè)的覆蓋先注冊(cè)的 else if (existingDefinition.getRole() < beanDefinition.getRole()) { // e.g. was ROLE_APPLICATION, now overriding with ROLE_SUPPORT or ROLE_INFRASTRUCTURE if (logger.isInfoEnabled()) { logger.info("Overriding user-defined bean definition for bean '" + beanName + "' with a framework-generated bean definition: replacing [" + existingDefinition + "] with [" + beanDefinition + "]"); } } else if (!beanDefinition.equals(existingDefinition)) { if (logger.isDebugEnabled()) { logger.debug("Overriding bean definition for bean '" + beanName + "' with a different definition: replacing [" + existingDefinition + "] with [" + beanDefinition + "]"); } } else { if (logger.isTraceEnabled()) { logger.trace("Overriding bean definition for bean '" + beanName + "' with an equivalent definition: replacing [" + existingDefinition + "] with [" + beanDefinition + "]"); } } // 注冊(cè)到容器，beanDefinitionMap 就是個(gè)容器 this.beanDefinitionMap.put(beanName, beanDefinition); } else { if (hasBeanCreationStarted()) { // Cannot modify startup-time collection elements anymore (for stable iteration) synchronized (this.beanDefinitionMap) { this.beanDefinitionMap.put(beanName, beanDefinition); List<String> updatedDefinitions = new ArrayList<>(this.beanDefinitionNames.size() + 1); updatedDefinitions.addAll(this.beanDefinitionNames); updatedDefinitions.add(beanName); this.beanDefinitionNames = updatedDefinitions; if (this.manualSingletonNames.contains(beanName)) { Set<String> updatedSingletons = new LinkedHashSet<>(this.manualSingletonNames); updatedSingletons.remove(beanName); this.manualSingletonNames = updatedSingletons; } } } else { // Still in startup registration phase this.beanDefinitionMap.put(beanName, beanDefinition); this.beanDefinitionNames.add(beanName); this.manualSingletonNames.remove(beanName); } this.frozenBeanDefinitionNames = null; } if (existingDefinition != null || containsSingleton(beanName)) { resetBeanDefinition(beanName); } }這個(gè)方法中對(duì)所需要加載的bean進(jìn)行校驗(yàn)，沒有問題的話就put到beanDefinitionMap中，beanDefinitionMap其實(shí)就是IOC.這樣我們的Bean就被加載到IOC容器中了。
本文鏈接：http://m.www897cc.com/showinfo-26-11758-0.html徹底搞懂Spring的Bean加載
聲明：本網(wǎng)頁內(nèi)容旨在傳播知識(shí)，若有侵權(quán)等問題請(qǐng)及時(shí)與本網(wǎng)聯(lián)系，我們將在第一時(shí)間刪除處理。郵件：2376512515@qq.com
Copyright ? 2016-2023 天津谷騏科技有限公司 版權(quán)所有 sitemap.xml
違法及侵權(quán)請(qǐng)聯(lián)系：2376512515@qq.com 津ICP備18001702號(hào)
津公網(wǎng)安備 12010102000574號(hào)