spring源码分析：spring生命周期二

接着上一篇我们看看具体是哪里的代码执行了。

1.初始化BeanFactoryPostProcessor

invokeBeanFactoryPostProcessors(beanFactory);-->PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(beanFactory, getBeanFactoryPostProcessors());List<BeanFactoryPostProcessor> nonOrderedPostProcessors = new ArrayList<>();        for (String postProcessorName : nonOrderedPostProcessorNames) {    //这里有一个getBean这里进行BeanFactoryPostProcessor的初始化操作        nonOrderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class));        }//这里执行BeanFactoryPostProcessor.postProcessBeanFactory    invokeBeanFactoryPostProcessors(nonOrderedPostProcessors, beanFactory);

执行BeanDefinitionRegistryPostProcessor.postProcessBeanDefinitionRegistry

    private static void invokeBeanDefinitionRegistryPostProcessors(            Collection<? extends BeanDefinitionRegistryPostProcessor> postProcessors, BeanDefinitionRegistry registry) {        for (BeanDefinitionRegistryPostProcessor postProcessor : postProcessors) {            postProcessor.postProcessBeanDefinitionRegistry(registry);        }    }

2.执行BeanFactoryPostProcessor的postProcessBeanFactory

private static void invokeBeanFactoryPostProcessors(            Collection<? extends BeanFactoryPostProcessor> postProcessors, ConfigurableListableBeanFactory beanFactory) {        for (BeanFactoryPostProcessor postProcessor : postProcessors) {            postProcessor.postProcessBeanFactory(beanFactory);        }    }

3.初始化BeanPostProcessor。

registerBeanPostProcessors(beanFactory);-->protected void registerBeanPostProcessors(ConfigurableListableBeanFactory beanFactory) {        PostProcessorRegistrationDelegate.registerBeanPostProcessors(beanFactory, this);    }    public static void registerBeanPostProcessors(            ConfigurableListableBeanFactory beanFactory, AbstractApplicationContext applicationContext) {....    // Now, register all regular BeanPostProcessors.        List<BeanPostProcessor> nonOrderedPostProcessors = new ArrayList<>();        for (String ppName : nonOrderedPostProcessorNames) {        //同样这里getBean对BeanPostProcessor进行实例化            BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class);            nonOrderedPostProcessors.add(pp);            if (pp instanceof MergedBeanDefinitionPostProcessor) {                internalPostProcessors.add(pp);            }        }....}

4.执行InstantiationAwareBeanPostProcessor.postProcessBeforeInstantiation
这里只以单例为例

AbstractBeanFactory.doGetBean(final String name, @Nullable final Class<T> requiredType,            @Nullable final Object[] args, boolean typeCheckOnly) throws BeansException {...    // Create bean instance.                if (mbd.isSingleton()) {                    sharedInstance = getSingleton(beanName, () -> {                        try {                            return createBean(beanName, mbd, args);                        }                        catch (BeansException ex) {                            // Explicitly remove instance from singleton cache: It might have been put there                            // eagerly by the creation process, to allow for circular reference resolution.                            // Also remove any beans that received a temporary reference to the bean.                            destroySingleton(beanName);                            throw ex;                        }                    });...}进入createBeanObject bean = resolveBeforeInstantiation(beanName, mbdToUse);protected Object resolveBeforeInstantiation(String beanName, RootBeanDefinition mbd) {        Object bean = null;        if (!Boolean.FALSE.equals(mbd.beforeInstantiationResolved)) {            // Make sure bean class is actually resolved at this point.            if (!mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) {                Class<?> targetType = determineTargetType(beanName, mbd);                if (targetType != null) {                    bean = applyBeanPostProcessorsBeforeInstantiation(targetType, beanName);                    if (bean != null) {                        bean = applyBeanPostProcessorsAfterInitialization(bean, beanName);                    }                }            }            mbd.beforeInstantiationResolved = (bean != null);        }        return bean;    }    protected Object applyBeanPostProcessorsBeforeInstantiation(Class<?> beanClass, String beanName) {        for (BeanPostProcessor bp : getBeanPostProcessors()) {            if (bp instanceof InstantiationAwareBeanPostProcessor) {                InstantiationAwareBeanPostProcessor ibp = (InstantiationAwareBeanPostProcessor) bp;                Object result = ibp.postProcessBeforeInstantiation(beanClass, beanName);                if (result != null) {                    return result;                }            }        }        return null;    }上面已经执行了postProcessBeforeInstantiation

5.执行bean的构造函数

进入Object beanInstance = doCreateBean(beanName, mbdToUse, args);if (instanceWrapper == null) {            //这里面进行初始化            instanceWrapper = createBeanInstance(beanName, mbd, args);        }

6.执行
postProcessBeforeInstantiation.postProcessPropertyValues

进入populateBean(beanName, mbd, instanceWrapper);if (hasInstAwareBpps || needsDepCheck) {            PropertyDescriptor[] filteredPds = filterPropertyDescriptorsForDependencyCheck(bw, mbd.allowCaching);            if (hasInstAwareBpps) {                for (BeanPostProcessor bp : getBeanPostProcessors()) {                    if (bp instanceof InstantiationAwareBeanPostProcessor) {//这里执行postProcessBeforeInstantiation.postProcessPropertyValues                        pvs = ibp.postProcessPropertyValues(pvs, filteredPds, bw.getWrappedInstance(), beanName);                        if (pvs == null) {                            return;                        }                    }                }            }            if (needsDepCheck) {                checkDependencies(beanName, mbd, filteredPds, pvs);            }        }applyPropertyValues(beanName, mbd, bw, pvs);

7.为bean注入属性

applyPropertyValues(beanName, mbd, bw, pvs);

8.执行bean实现的有关Aware接口

进入  exposedObject = initializeBean(beanName, exposedObject, mbd);//这里给Aware赋予aware接口的能力invokeAwareMethods(beanName, bean);

9.执行BeanPostProcessor.postProcessBeforeInitialization

if (mbd == null || !mbd.isSynthetic()) {            wrappedBean = applyBeanPostProcessorsBeforeInitialization(wrappedBean, beanName);        }    public Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName)            throws BeansException {        Object result = existingBean;        for (BeanPostProcessor beanProcessor : getBeanPostProcessors()) {            Object current = beanProcessor.postProcessBeforeInitialization(result, beanName);            if (current == null) {                return result;            }            result = current;        }        return result;    }

10.执行@PostConstrut初始化方法

执行CommonAnnotationBeanPostProcessor.postProcessBeforeInitialization具体为什么会调用该方法放在后面统一讲解

11.执行InitializingBean.

进入invokeInitMethods(beanName, wrappedBean, mbd);protected void invokeInitMethods(String beanName, final Object bean, @Nullable RootBeanDefinition mbd)            throws Throwable {        boolean isInitializingBean = (bean instanceof InitializingBean);        if (isInitializingBean && (mbd == null || !mbd.isExternallyManagedInitMethod("afterPropertiesSet"))) {            if (logger.isDebugEnabled()) {                logger.debug("Invoking afterPropertiesSet() on bean with name '" + beanName + "'");            }            if (System.getSecurityManager() != null) {                try {                    AccessController.doPrivileged((PrivilegedExceptionAction<Object>) () -> {                        ((InitializingBean) bean).afterPropertiesSet();                        return null;                    }, getAccessControlContext());                }                catch (PrivilegedActionException pae) {                    throw pae.getException();                }            }            else {            //这里调用                ((InitializingBean) bean).afterPropertiesSet();            }        }        if (mbd != null) {            String initMethodName = mbd.getInitMethodName();            if (StringUtils.hasLength(initMethodName) &&                    !(isInitializingBean && "afterPropertiesSet".equals(initMethodName)) &&                    !mbd.isExternallyManagedInitMethod(initMethodName)) {                invokeCustomInitMethod(beanName, bean, mbd);            }        }    }

12.执行xml的init-method

if (mbd != null) {            String initMethodName = mbd.getInitMethodName();            if (StringUtils.hasLength(initMethodName) &&                    !(isInitializingBean && "afterPropertiesSet".equals(initMethodName)) &&                    !mbd.isExternallyManagedInitMethod(initMethodName)) {                invokeCustomInitMethod(beanName, bean, mbd);            }        }

13.执行BeanPostProcessor.postProcessAfterInitialization

if (mbd == null || !mbd.isSynthetic()) {            wrappedBean = applyBeanPostProcessorsAfterInitialization(wrappedBean, beanName);        }@Override    public Object applyBeanPostProcessorsAfterInitialization(Object existingBean, String beanName)            throws BeansException {        Object result = existingBean;        for (BeanPostProcessor beanProcessor : getBeanPostProcessors()) {            Object current = beanProcessor.postProcessAfterInitialization(result, beanName);            if (current == null) {                return result;            }            result = current;        }        return result;    }

以上的代码以AbstractApplicationContext。。refresh和AbstractBeanFactory.doGetBean为入口一步步跟均能找到。

上篇讲解了spring生命周期，这篇讲解了spring哪里具体实现。下一篇就讲解应用了，注解如何实现，例如@Configutation,@Import,@PostConstrut等。