public Object postProcessBeforeInitialization(Object bean, String beanName)throws BeansException {// 1. 如果已经被RefreshScope修饰了,也会自动更新就不用在处理了。 	if (isRefreshScoped(beanName)) {return bean;}ConfigurationProperties annotation = AnnotationUtils.findAnnotation(bean.getClass(), ConfigurationProperties.class);if (annotation != null) {this.beans.put(beanName, bean);}else if (this.metaData != null) {annotation = this.metaData.findFactoryAnnotation(beanName,ConfigurationProperties.class);if (annotation != null) {this.beans.put(beanName, bean);}}return bean;}

// 接受事件public void onApplicationEvent(EnvironmentChangeEvent event) {if (this.applicationContext.equals(event.getSource())// Backwards compatible|| event.getKeys().equals(event.getSource())) {rebind();}}// 重新绑定public boolean rebind(String name) {if (!this.beans.getBeanNames().contains(name)) {return false;}if (this.applicationContext != null) {try {Object bean = this.applicationContext.getBean(name);if (AopUtils.isAopProxy(bean)) {bean = ProxyUtils.getTargetObject(bean);}if (bean != null) {this.applicationContext.getAutowireCapableBeanFactory().destroyBean(bean);this.applicationContext.getAutowireCapableBeanFactory().initializeBean(bean, name);return true;}}catch (RuntimeException e) {this.errors.put(name, e);throw e;}catch (Exception e) {this.errors.put(name, e);throw new IllegalStateException("Cannot rebind to " + name, e);}}return false;}

public class GenericScope implements Scope, BeanFactoryPostProcessor,BeanDefinitionRegistryPostProcessor, DisposableBean {}
public class RefreshScope extends GenericScope implements ApplicationContextAware,ApplicationListener<ContextRefreshedEvent>, Ordered {	
}		

protected <T> T doGetBean(final String name, @Nullable final Class<T> requiredType,@Nullable final Object[] args, boolean typeCheckOnly) throws BeansException {...// 创建单例逻辑if (mbd.isSingleton()) {...bean = getObjectForBeanInstance(sharedInstance, name, beanName, mbd);}// 创建原型逻辑else if (mbd.isPrototype()) {...bean = getObjectForBeanInstance(prototypeInstance, name, beanName, mbd);}else {// 创建域对象// refreshString scopeName = mbd.getScope();// RefreshScopefinal Scope scope = this.scopes.get(scopeName);if (scope == null) {throw new IllegalStateException("No Scope registered for scope name '" + scopeName + "'");}try {Object scopedInstance = scope.get(beanName, () -> {beforePrototypeCreation(beanName);try {return createBean(beanName, mbd, args);}finally {afterPrototypeCreation(beanName);}});bean = getObjectForBeanInstance(scopedInstance, name, beanName, mbd);}}}}return (T) bean;}

public interface Scope {Object get(String name, ObjectFactory<?> objectFactory); 
}
public class GenericScope implements Scope, BeanFactoryPostProcessor,BeanDefinitionRegistryPostProcessor, DisposableBean {}
public class RefreshScope extends GenericScope implements ApplicationContextAware,ApplicationListener<ContextRefreshedEvent>, Ordered {}		

public class RefreshEventListener implements SmartApplicationListener {private ContextRefresher refresh;@Overridepublic void onApplicationEvent(ApplicationEvent event) {if (event instanceof ApplicationReadyEvent) {handle((ApplicationReadyEvent) event);}else if (event instanceof RefreshEvent) {handle((RefreshEvent) event);}}public void handle(ApplicationReadyEvent event) {this.ready.compareAndSet(false, true);}public void handle(RefreshEvent event) {if (this.ready.get()) { // don't handle events before app is readylog.debug("Event received " + event.getEventDesc());Set<String> keys = this.refresh.refresh();log.info("Refresh keys changed: " + keys);}}
}

public class ContextRefresher {public synchronized Set<String> refresh() {Set<String> keys = refreshEnvironment();this.scope.refreshAll();return keys;}public synchronized Set<String> refreshEnvironment() {Map<String, Object> before = extract(this.context.getEnvironment().getPropertySources());addConfigFilesToEnvironment();Set<String> keys = changes(before,extract(this.context.getEnvironment().getPropertySources())).keySet();this.context.publishEvent(new EnvironmentChangeEvent(this.context, keys));return keys;}
}

public class ScopedProxyFactoryBean extends ProxyConfigimplements FactoryBean<Object>, BeanFactoryAware, AopInfrastructureBean {private Object proxy;	private final SimpleBeanTargetSource scopedTargetSource = new SimpleBeanTargetSource();@Overridepublic void setBeanFactory(BeanFactory beanFactory) {...ProxyFactory pf = new ProxyFactory();pf.copyFrom(this);pf.setTargetSource(this.scopedTargetSource);this.proxy = pf.getProxy(cbf.getBeanClassLoader());}
}		public class SimpleBeanTargetSource extends AbstractBeanFactoryBasedTargetSource {@Overridepublic Object getTarget() throws Exception {return getBeanFactory().getBean(getTargetBeanName());}
}

public class SpringValueProcessor extends ApolloProcessor implements BeanFactoryPostProcessor, BeanFactoryAware {protected void processField(Object bean, String beanName, Field field) {// register @Value on fieldValue value = field.getAnnotation(Value.class);if (value == null) {return;}Set<String> keys = placeholderHelper.extractPlaceholderKeys(value.value());if (keys.isEmpty()) {return;}for (String key : keys) {SpringValue springValue = new SpringValue(key, value.value(), bean, beanName, field, false);springValueRegistry.register(beanFactory, key, springValue);logger.debug("Monitoring {}", springValue);}}
}

public class AutoUpdateConfigChangeListener implements ConfigChangeListener{@Overridepublic void onChange(ConfigChangeEvent changeEvent) {Set<String> keys = changeEvent.changedKeys();if (CollectionUtils.isEmpty(keys)) {return;}for (String key : keys) {// 1. check whether the changed key is relevantCollection<SpringValue> targetValues = springValueRegistry.get(beanFactory, key);if (targetValues == null || targetValues.isEmpty()) {continue;}// 2. update the valuefor (SpringValue val : targetValues) {updateSpringValue(val);}}}
}

public class SpringValue {public void update(Object newVal) throws IllegalAccessException, InvocationTargetException {if (isField()) {injectField(newVal);} else {injectMethod(newVal);}}private void injectField(Object newVal) throws IllegalAccessException {Object bean = beanRef.get();if (bean == null) {return;}boolean accessible = field.isAccessible();field.setAccessible(true);field.set(bean, newVal);field.setAccessible(accessible);}
}