AmyliaY
5 years ago
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GitHub
commit
f13fa64ef7
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# Spring initApplicationEventMulticaster
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- Author: [HuiFer](https://github.com/huifer)
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- 源码阅读仓库: [huifer-spring](https://github.com/huifer/spring-framework-read)
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## demo
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```java
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package com.huifer.source.spring.applicationListener;
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import org.springframework.context.ApplicationEvent;
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import org.springframework.context.ApplicationListener;
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public class DemoApplicationListener implements ApplicationListener {
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@Override
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public void onApplicationEvent(ApplicationEvent event) {
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System.out.println("com.huifer.source.spring.applicationListener.DemoApplicationListener.onApplicationEvent");
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}
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}
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```
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```XML
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<?xml version="1.0" encoding="UTF-8"?>
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<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xmlns="http://www.springframework.org/schema/beans"
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xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
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<bean id="demoApplicationListener" class="com.huifer.source.spring.applicationListener.DemoApplicationListener"/>
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</beans>
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```
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```JAVA
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public class ListenerSourceCode {
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public static void main(String[] args) {
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ApplicationContext context = new ClassPathXmlApplicationContext("Listener-demo.xml");
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}
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}
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```
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## 初始化入口
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- `org.springframework.context.support.AbstractApplicationContext.refresh`中的`initApplicationEventMulticaster`方法
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```java
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protected void initApplicationEventMulticaster() {
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ConfigurableListableBeanFactory beanFactory = getBeanFactory();
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// 判断是否存在名字applicationEventMulticaster的bean
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if (beanFactory.containsLocalBean(APPLICATION_EVENT_MULTICASTER_BEAN_NAME)) {
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this.applicationEventMulticaster =
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beanFactory.getBean(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, ApplicationEventMulticaster.class);
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if (logger.isTraceEnabled()) {
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logger.trace("Using ApplicationEventMulticaster [" + this.applicationEventMulticaster + "]");
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}
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}
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else {
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// 创建一个
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this.applicationEventMulticaster = new SimpleApplicationEventMulticaster(beanFactory);
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beanFactory.registerSingleton(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, this.applicationEventMulticaster);
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if (logger.isTraceEnabled()) {
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logger.trace("No '" + APPLICATION_EVENT_MULTICASTER_BEAN_NAME + "' bean, using " +
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"[" + this.applicationEventMulticaster.getClass().getSimpleName() + "]");
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}
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}
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}
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```
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## 注册
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```JAVA
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protected void registerListeners() {
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// Register statically specified listeners first.
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// 读取 ApplicationListener
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for (ApplicationListener<?> listener : getApplicationListeners()) {
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getApplicationEventMulticaster().addApplicationListener(listener);
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}
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// Do not initialize FactoryBeans here: We need to leave all regular beans
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// uninitialized to let post-processors apply to them!
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/**
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* 寻找类型为{@link ApplicationListener} 的beanName,目标文件为用户配置文件
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*/
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String[] listenerBeanNames = getBeanNamesForType(ApplicationListener.class, true, false);
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for (String listenerBeanName : listenerBeanNames) {
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/**
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* 1. 获取 {@link applicationEventMulticaster}
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* 2. 添加监听器名称
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*/
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getApplicationEventMulticaster().addApplicationListenerBean(listenerBeanName);
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}
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// Publish early application events now that we finally have a multicaster...
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Set<ApplicationEvent> earlyEventsToProcess = this.earlyApplicationEvents;
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this.earlyApplicationEvents = null;
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if (earlyEventsToProcess != null) {
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for (ApplicationEvent earlyEvent : earlyEventsToProcess) {
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getApplicationEventMulticaster().multicastEvent(earlyEvent);
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}
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}
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}
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```
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## finishRefresh 发布
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```java
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protected void finishRefresh() {
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// Clear context-level resource caches (such as ASM metadata from scanning).
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clearResourceCaches();
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// Initialize lifecycle processor for this context.
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initLifecycleProcessor();
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// Propagate refresh to lifecycle processor first.
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getLifecycleProcessor().onRefresh();
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// Publish the final event.
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// 发布事件做处理
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publishEvent(new ContextRefreshedEvent(this));
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// Participate in LiveBeansView MBean, if active.
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LiveBeansView.registerApplicationContext(this);
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}
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```
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- `org.springframework.context.support.AbstractApplicationContext#publishEvent(org.springframework.context.ApplicationEvent)`
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- `org.springframework.context.support.AbstractApplicationContext#publishEvent(java.lang.Object, org.springframework.core.ResolvableType)`
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```java
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protected void publishEvent(Object event, @Nullable ResolvableType eventType) {
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Assert.notNull(event, "Event must not be null");
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// Decorate event as an ApplicationEvent if necessary
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ApplicationEvent applicationEvent;
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if (event instanceof ApplicationEvent) {
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applicationEvent = (ApplicationEvent) event;
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}
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else {
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applicationEvent = new PayloadApplicationEvent<>(this, event);
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if (eventType == null) {
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eventType = ((PayloadApplicationEvent<?>) applicationEvent).getResolvableType();
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}
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}
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// Multicast right now if possible - or lazily once the multicaster is initialized
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if (this.earlyApplicationEvents != null) {
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this.earlyApplicationEvents.add(applicationEvent);
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}
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else {
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/**
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* 执行监听事件
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* {@link ApplicationEventMulticaster} ->{@link SimpleApplicationEventMulticaster}
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*/
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getApplicationEventMulticaster().multicastEvent(applicationEvent, eventType);
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}
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// Publish event via parent context as well...
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if (this.parent != null) {
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if (this.parent instanceof AbstractApplicationContext) {
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((AbstractApplicationContext) this.parent).publishEvent(event, eventType);
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}
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else {
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this.parent.publishEvent(event);
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}
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}
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}
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```
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- 执行监听方法
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```java
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protected void invokeListener(ApplicationListener<?> listener, ApplicationEvent event) {
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ErrorHandler errorHandler = getErrorHandler();
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if (errorHandler != null) {
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try {
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doInvokeListener(listener, event);
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}
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catch (Throwable err) {
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errorHandler.handleError(err);
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}
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}
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else {
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doInvokeListener(listener, event);
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}
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}
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```
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```java
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@SuppressWarnings({"rawtypes", "unchecked"})
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private void doInvokeListener(ApplicationListener listener, ApplicationEvent event) {
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try {
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// 最后调用方法
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listener.onApplicationEvent(event);
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}
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catch (ClassCastException ex) {
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String msg = ex.getMessage();
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if (msg == null || matchesClassCastMessage(msg, event.getClass())) {
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// Possibly a lambda-defined listener which we could not resolve the generic event type for
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// -> let's suppress the exception and just log a debug message.
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Log logger = LogFactory.getLog(getClass());
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if (logger.isTraceEnabled()) {
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logger.trace("Non-matching event type for listener: " + listener, ex);
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}
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}
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else {
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throw ex;
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}
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}
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}
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```
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@ -0,0 +1,403 @@
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# Spring 自定义属性解析器
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- Author: [HuiFer](https://github.com/huifer)
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- 源码阅读仓库: [huifer-spring](https://github.com/huifer/spring-framework-read)
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## 用例
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```xml
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<?xml version="1.0" encoding="UTF-8"?>
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<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xmlns="http://www.springframework.org/schema/beans"
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xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
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<bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
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<property name="propertyEditorRegistrars">
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<list>
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<bean class="com.huifer.source.spring.bean.DatePropertyRegister"/>
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</list>
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</property>
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<property name="customEditors">
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<map>
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<entry key="java.util.Date" value="com.huifer.source.spring.bean.DatePropertyEditor">
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</entry>
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</map>
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</property>
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</bean>
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<bean id="apple" class="com.huifer.source.spring.bean.Apple">
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<property name="date" value="2020-01-01 01:01:01"/>
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</bean>
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</beans>
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```
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```java
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public class DatePropertyRegister implements PropertyEditorRegistrar {
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@Override
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public void registerCustomEditors(PropertyEditorRegistry registry) {
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registry.registerCustomEditor(Date.class, new CustomDateEditor(
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new SimpleDateFormat("yyyy-MM-dd"), true)
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);
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}
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}
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```
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```java
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public class DatePropertyEditor extends PropertyEditorSupport {
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private String format = "yyyy-MM-dd";
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public String getFormat() {
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return format;
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}
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public void setFormat(String format) {
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this.format = format;
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}
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@Override
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public void setAsText(String text) throws IllegalArgumentException {
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System.out.println(text);
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SimpleDateFormat sdf = new SimpleDateFormat(format);
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try {
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Date date = sdf.parse(text);
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this.setValue(date);
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} catch (Exception e) {
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e.printStackTrace();
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}
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}
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}
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```
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## PropertyEditorRegistrar解析
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- 直接在`DatePropertyRegister`打上断点进行查看注册流程
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直接看调用堆栈获取调用层次
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```java
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@Override
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public void registerCustomEditor(Class<?> requiredType, PropertyEditor propertyEditor) {
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registerCustomEditor(requiredType, null, propertyEditor);
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}
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```
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```java
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@Override
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public void registerCustomEditor(@Nullable Class<?> requiredType, @Nullable String propertyPath, PropertyEditor propertyEditor) {
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if (requiredType == null && propertyPath == null) {
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throw new IllegalArgumentException("Either requiredType or propertyPath is required");
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}
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if (propertyPath != null) {
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if (this.customEditorsForPath == null) {
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this.customEditorsForPath = new LinkedHashMap<>(16);
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}
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this.customEditorsForPath.put(propertyPath, new CustomEditorHolder(propertyEditor, requiredType));
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}
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else {
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if (this.customEditors == null) {
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this.customEditors = new LinkedHashMap<>(16);
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}
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// 放入 customEditors map对象中
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this.customEditors.put(requiredType, propertyEditor);
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this.customEditorCache = null;
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}
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}
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```
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- `PropertyEditorRegistrySupport`
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此处对象是通过`DatePropertyRegister`传递的
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- `org.springframework.beans.factory.support.AbstractBeanFactory#registerCustomEditors`
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```java
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protected void registerCustomEditors(PropertyEditorRegistry registry) {
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PropertyEditorRegistrySupport registrySupport =
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(registry instanceof PropertyEditorRegistrySupport ? (PropertyEditorRegistrySupport) registry : null);
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if (registrySupport != null) {
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registrySupport.useConfigValueEditors();
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}
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if (!this.propertyEditorRegistrars.isEmpty()) {
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for (PropertyEditorRegistrar registrar : this.propertyEditorRegistrars) {
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try {
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/**
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* {@link ResourceEditorRegistrar#registerCustomEditors(org.springframework.beans.PropertyEditorRegistry)}或者
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* {@link PropertyEditorRegistrar#registerCustomEditors(org.springframework.beans.PropertyEditorRegistry)}
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*/
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registrar.registerCustomEditors(registry);
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}
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catch (BeanCreationException ex) {
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Throwable rootCause = ex.getMostSpecificCause();
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if (rootCause instanceof BeanCurrentlyInCreationException) {
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BeanCreationException bce = (BeanCreationException) rootCause;
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String bceBeanName = bce.getBeanName();
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if (bceBeanName != null && isCurrentlyInCreation(bceBeanName)) {
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if (logger.isDebugEnabled()) {
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logger.debug("PropertyEditorRegistrar [" + registrar.getClass().getName() +
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"] failed because it tried to obtain currently created bean '" +
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ex.getBeanName() + "': " + ex.getMessage());
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}
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onSuppressedException(ex);
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continue;
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}
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}
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throw ex;
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}
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}
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}
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if (!this.customEditors.isEmpty()) {
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this.customEditors.forEach((requiredType, editorClass) ->
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registry.registerCustomEditor(requiredType, BeanUtils.instantiateClass(editorClass)));
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}
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}
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```
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- `void registerCustomEditors(PropertyEditorRegistry registry);` 用例中编写的`DatePropertyRegister`正好有这个方法的实现
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·
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- 在`AbstractBeanFactory`中查看变量
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- 为什么最后结果变成`com.huifer.source.spring.bean.DatePropertyEditor`
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看配置文件
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```xml
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<property name="customEditors">
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<map>
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<entry key="java.util.Date" value="com.huifer.source.spring.bean.DatePropertyEditor">
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</entry>
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</map>
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</property>
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```
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- 对应的set方法
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```java
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public void setCustomEditors(Map<Class<?>, Class<? extends PropertyEditor>> customEditors) {
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this.customEditors = customEditors;
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}
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```
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## applyPropertyValues
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- 应用属性值
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```java
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protected void applyPropertyValues(String beanName, BeanDefinition mbd, BeanWrapper bw, PropertyValues pvs) {
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if (pvs.isEmpty()) {
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return;
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}
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if (System.getSecurityManager() != null && bw instanceof BeanWrapperImpl) {
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((BeanWrapperImpl) bw).setSecurityContext(getAccessControlContext());
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}
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MutablePropertyValues mpvs = null;
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// 没有解析的属性
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List<PropertyValue> original;
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if (pvs instanceof MutablePropertyValues) {
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mpvs = (MutablePropertyValues) pvs;
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if (mpvs.isConverted()) {
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//MutablePropertyValues 对象中存在转换后对象直接赋值
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// Shortcut: use the pre-converted values as-is.
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try {
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bw.setPropertyValues(mpvs);
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return;
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}
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catch (BeansException ex) {
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throw new BeanCreationException(
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mbd.getResourceDescription(), beanName, "Error setting property values", ex);
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}
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}
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original = mpvs.getPropertyValueList();
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}
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else {
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original = Arrays.asList(pvs.getPropertyValues());
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}
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// 自定义转换器
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TypeConverter converter = getCustomTypeConverter();
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if (converter == null) {
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converter = bw;
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}
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// 创建BeanDefinitionValueResolver
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BeanDefinitionValueResolver valueResolver = new BeanDefinitionValueResolver(this, beanName, mbd, converter);
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// Create a deep copy, resolving any references for values.
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// 解析后的对象集合
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List<PropertyValue> deepCopy = new ArrayList<>(original.size());
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boolean resolveNecessary = false;
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for (PropertyValue pv : original) {
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// 解析过的属性
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if (pv.isConverted()) {
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deepCopy.add(pv);
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}
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// 没有解析过的属性
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else {
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// 属性名称
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String propertyName = pv.getName();
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// 属性值,直接读取到的
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Object originalValue = pv.getValue();
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// 解析值
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Object resolvedValue = valueResolver.resolveValueIfNecessary(pv, originalValue);
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Object convertedValue = resolvedValue;
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/**
|
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* 1. isWritableProperty: 属性可写
|
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* 2. isNestedOrIndexedProperty: 是否循环嵌套
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||||
*/
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||||
boolean convertible = bw.isWritableProperty(propertyName) &&
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!PropertyAccessorUtils.isNestedOrIndexedProperty(propertyName);
|
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if (convertible) {
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// 转换器解析
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convertedValue = convertForProperty(resolvedValue, propertyName, bw, converter);
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}
|
||||
// Possibly store converted value in merged bean definition,
|
||||
// in order to avoid re-conversion for every created bean instance.
|
||||
if (resolvedValue == originalValue) {
|
||||
if (convertible) {
|
||||
// 设置解析值
|
||||
pv.setConvertedValue(convertedValue);
|
||||
}
|
||||
deepCopy.add(pv);
|
||||
}
|
||||
// 类型解析
|
||||
else if (convertible && originalValue instanceof TypedStringValue &&
|
||||
!((TypedStringValue) originalValue).isDynamic() &&
|
||||
!(convertedValue instanceof Collection || ObjectUtils.isArray(convertedValue))) {
|
||||
pv.setConvertedValue(convertedValue);
|
||||
deepCopy.add(pv);
|
||||
}
|
||||
else {
|
||||
resolveNecessary = true;
|
||||
deepCopy.add(new PropertyValue(pv, convertedValue));
|
||||
}
|
||||
}
|
||||
}
|
||||
if (mpvs != null && !resolveNecessary) {
|
||||
// 转换成功的标记方法
|
||||
mpvs.setConverted();
|
||||
}
|
||||
|
||||
// Set our (possibly massaged) deep copy.
|
||||
try {
|
||||
bw.setPropertyValues(new MutablePropertyValues(deepCopy));
|
||||
}
|
||||
catch (BeansException ex) {
|
||||
throw new BeanCreationException(
|
||||
mbd.getResourceDescription(), beanName, "Error setting property values", ex);
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
- 属性值解析
|
||||
|
||||
|
||||
|
||||
```JAVA
|
||||
@Nullable
|
||||
private Object convertForProperty(
|
||||
@Nullable Object value, String propertyName, BeanWrapper bw, TypeConverter converter) {
|
||||
|
||||
if (converter instanceof BeanWrapperImpl) {
|
||||
return ((BeanWrapperImpl) converter).convertForProperty(value, propertyName);
|
||||
}
|
||||
else {
|
||||
PropertyDescriptor pd = bw.getPropertyDescriptor(propertyName);
|
||||
MethodParameter methodParam = BeanUtils.getWriteMethodParameter(pd);
|
||||
return converter.convertIfNecessary(value, pd.getPropertyType(), methodParam);
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
```JAVA
|
||||
private Object doConvertTextValue(@Nullable Object oldValue, String newTextValue, PropertyEditor editor) {
|
||||
try {
|
||||
editor.setValue(oldValue);
|
||||
}
|
||||
catch (Exception ex) {
|
||||
if (logger.isDebugEnabled()) {
|
||||
logger.debug("PropertyEditor [" + editor.getClass().getName() + "] does not support setValue call", ex);
|
||||
}
|
||||
// Swallow and proceed.
|
||||
}
|
||||
// 调用子类实现方法
|
||||
editor.setAsText(newTextValue);
|
||||
return editor.getValue();
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
- 调用用例编写的方法
|
||||
|
||||
```JAVA
|
||||
@Override
|
||||
public void setAsText(String text) throws IllegalArgumentException {
|
||||
System.out.println(text);
|
||||
SimpleDateFormat sdf = new SimpleDateFormat(format);
|
||||
try {
|
||||
Date date = sdf.parse(text);
|
||||
this.setValue(date);
|
||||
} catch (Exception e) {
|
||||
e.printStackTrace();
|
||||
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
该值也是这个方法的返回`org.springframework.beans.TypeConverterDelegate#convertIfNecessary(java.lang.String, java.lang.Object, java.lang.Object, java.lang.Class<T>, org.springframework.core.convert.TypeDescriptor)`
|
||||
|
||||
@ -0,0 +1,210 @@
|
||||
# Spring MessageSource
|
||||
- Author: [HuiFer](https://github.com/huifer)
|
||||
- 源码阅读仓库: [huifer-spring](https://github.com/huifer/spring-framework-read)
|
||||
|
||||
## 初始化入口
|
||||
- `org.springframework.context.support.AbstractApplicationContext.refresh`方法有`initMessageSource()`方法进行了`MessageSource`初始化
|
||||
|
||||
|
||||
|
||||
```java
|
||||
protected void initMessageSource() {
|
||||
ConfigurableListableBeanFactory beanFactory = getBeanFactory();
|
||||
// 判断是否含有 messageSource
|
||||
if (beanFactory.containsLocalBean(MESSAGE_SOURCE_BEAN_NAME)) {
|
||||
// 读取xml配置文件中 id="messageSource"的数据
|
||||
this.messageSource = beanFactory.getBean(MESSAGE_SOURCE_BEAN_NAME, MessageSource.class);
|
||||
// Make MessageSource aware of parent MessageSource.
|
||||
if (this.parent != null && this.messageSource instanceof HierarchicalMessageSource) {
|
||||
HierarchicalMessageSource hms = (HierarchicalMessageSource) this.messageSource;
|
||||
if (hms.getParentMessageSource() == null) {
|
||||
// Only set parent context as parent MessageSource if no parent MessageSource
|
||||
// registered already.
|
||||
hms.setParentMessageSource(getInternalParentMessageSource());
|
||||
}
|
||||
}
|
||||
if (logger.isTraceEnabled()) {
|
||||
logger.trace("Using MessageSource [" + this.messageSource + "]");
|
||||
}
|
||||
}
|
||||
else {
|
||||
// Use empty MessageSource to be able to accept getMessage calls.
|
||||
// 没有使用默认的 DelegatingMessageSource
|
||||
DelegatingMessageSource dms = new DelegatingMessageSource();
|
||||
dms.setParentMessageSource(getInternalParentMessageSource());
|
||||
this.messageSource = dms;
|
||||
// 注册单例对象
|
||||
beanFactory.registerSingleton(MESSAGE_SOURCE_BEAN_NAME, this.messageSource);
|
||||
if (logger.isTraceEnabled()) {
|
||||
logger.trace("No '" + MESSAGE_SOURCE_BEAN_NAME + "' bean, using [" + this.messageSource + "]");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
读取xml配置文件
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
## getMessage
|
||||
|
||||
- `org.springframework.context.support.AbstractApplicationContext#getMessage(java.lang.String, java.lang.Object[], java.util.Locale)`
|
||||
|
||||
```java
|
||||
@Override
|
||||
public String getMessage(String code, @Nullable Object[] args, Locale locale) throws NoSuchMessageException {
|
||||
return getMessageSource().getMessage(code, args, locale);
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
- `org.springframework.context.support.AbstractMessageSource#getMessage(java.lang.String, java.lang.Object[], java.util.Locale)`
|
||||
|
||||
```java
|
||||
@Override
|
||||
public final String getMessage(String code, @Nullable Object[] args, Locale locale) throws NoSuchMessageException {
|
||||
// 获取对应的信息
|
||||
String msg = getMessageInternal(code, args, locale);
|
||||
if (msg != null) {
|
||||
return msg;
|
||||
}
|
||||
// 默认信息 null
|
||||
String fallback = getDefaultMessage(code);
|
||||
if (fallback != null) {
|
||||
return fallback;
|
||||
}
|
||||
throw new NoSuchMessageException(code, locale);
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
- 两个方法
|
||||
|
||||
1. `org.springframework.context.support.AbstractMessageSource#getDefaultMessage(java.lang.String)`
|
||||
|
||||
```java
|
||||
@Nullable
|
||||
protected String getDefaultMessage(String code) {
|
||||
// 判断是否使用默认值
|
||||
if (isUseCodeAsDefaultMessage()) {
|
||||
return code;
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
- 返回code本身或者`null`
|
||||
|
||||
2. `org.springframework.context.support.AbstractMessageSource#getMessageInternal`
|
||||
|
||||
```JAVA
|
||||
@Nullable
|
||||
protected String getMessageInternal(@Nullable String code, @Nullable Object[] args, @Nullable Locale locale) {
|
||||
if (code == null) {
|
||||
return null;
|
||||
}
|
||||
if (locale == null) {
|
||||
// 获取语言默认值
|
||||
locale = Locale.getDefault();
|
||||
}
|
||||
Object[] argsToUse = args;
|
||||
|
||||
if (!isAlwaysUseMessageFormat() && ObjectUtils.isEmpty(args)) {
|
||||
// Optimized resolution: no arguments to apply,
|
||||
// therefore no MessageFormat needs to be involved.
|
||||
// Note that the default implementation still uses MessageFormat;
|
||||
// this can be overridden in specific subclasses.
|
||||
String message = resolveCodeWithoutArguments(code, locale);
|
||||
if (message != null) {
|
||||
return message;
|
||||
}
|
||||
}
|
||||
|
||||
else {
|
||||
// Resolve arguments eagerly, for the case where the message
|
||||
// is defined in a parent MessageSource but resolvable arguments
|
||||
// are defined in the child MessageSource.
|
||||
argsToUse = resolveArguments(args, locale);
|
||||
|
||||
MessageFormat messageFormat = resolveCode(code, locale);
|
||||
if (messageFormat != null) {
|
||||
synchronized (messageFormat) {
|
||||
return messageFormat.format(argsToUse);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Check locale-independent common messages for the given message code.
|
||||
Properties commonMessages = getCommonMessages();
|
||||
if (commonMessages != null) {
|
||||
String commonMessage = commonMessages.getProperty(code);
|
||||
if (commonMessage != null) {
|
||||
return formatMessage(commonMessage, args, locale);
|
||||
}
|
||||
}
|
||||
|
||||
// Not found -> check parent, if any.
|
||||
return getMessageFromParent(code, argsToUse, locale);
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
- `org.springframework.context.support.ResourceBundleMessageSource#resolveCodeWithoutArguments`
|
||||
|
||||
```JAVA
|
||||
@Override
|
||||
protected String resolveCodeWithoutArguments(String code, Locale locale) {
|
||||
Set<String> basenames = getBasenameSet();
|
||||
for (String basename : basenames) {
|
||||
// 加载 basename
|
||||
ResourceBundle bundle = getResourceBundle(basename, locale);
|
||||
if (bundle != null) {
|
||||
// 从basename对应的文件中获取对应的值
|
||||
String result = getStringOrNull(bundle, code);
|
||||
if (result != null) {
|
||||
return result;
|
||||
}
|
||||
}
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
- 加载后截图
|
||||
|
||||
获取方法`String result = getStringOrNull(bundle, code);`就是map获取
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
- 没有配置文件的情况
|
||||
|
||||
|
||||
@ -0,0 +1,62 @@
|
||||
# Spring OrderUtils
|
||||
- Author: [HuiFer](https://github.com/huifer)
|
||||
- 源码阅读仓库: [huifer-spring](https://github.com/huifer/spring-framework-read)
|
||||
- `org.springframework.core.annotation.OrderUtils`主要方法如下
|
||||
1. getOrder
|
||||
1. getPriority
|
||||
|
||||
- 测试类`org.springframework.core.annotation.OrderUtilsTests`
|
||||
|
||||
```java
|
||||
@Nullable
|
||||
public static Integer getOrder(Class<?> type) {
|
||||
// 缓存中获取
|
||||
Object cached = orderCache.get(type);
|
||||
if (cached != null) {
|
||||
// 返回 int
|
||||
return (cached instanceof Integer ? (Integer) cached : null);
|
||||
}
|
||||
/**
|
||||
* 注解工具类,寻找{@link Order}注解
|
||||
*/
|
||||
Order order = AnnotationUtils.findAnnotation(type, Order.class);
|
||||
Integer result;
|
||||
if (order != null) {
|
||||
// 返回
|
||||
result = order.value();
|
||||
} else {
|
||||
result = getPriority(type);
|
||||
}
|
||||
// key: 类名,value: intValue
|
||||
orderCache.put(type, (result != null ? result : NOT_ANNOTATED));
|
||||
return result;
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
```java
|
||||
@Nullable
|
||||
public static Integer getPriority(Class<?> type) {
|
||||
if (priorityAnnotationType == null) {
|
||||
return null;
|
||||
}
|
||||
// 缓存中获取
|
||||
Object cached = priorityCache.get(type);
|
||||
if (cached != null) {
|
||||
// 不为空返回
|
||||
return (cached instanceof Integer ? (Integer) cached : null);
|
||||
}
|
||||
// 注解工具获取注解
|
||||
Annotation priority = AnnotationUtils.findAnnotation(type, priorityAnnotationType);
|
||||
Integer result = null;
|
||||
if (priority != null) {
|
||||
// 获取 value
|
||||
result = (Integer) AnnotationUtils.getValue(priority);
|
||||
}
|
||||
// 向缓存插入数据
|
||||
priorityCache.put(type, (result != null ? result : NOT_ANNOTATED));
|
||||
return result;
|
||||
}
|
||||
|
||||
```
|
||||
|
After Width: | Height: | Size: 35 KiB |
|
After Width: | Height: | Size: 53 KiB |
|
After Width: | Height: | Size: 34 KiB |
|
After Width: | Height: | Size: 42 KiB |
|
After Width: | Height: | Size: 49 KiB |
|
After Width: | Height: | Size: 11 KiB |
|
After Width: | Height: | Size: 53 KiB |
|
After Width: | Height: | Size: 14 KiB |
|
After Width: | Height: | Size: 14 KiB |
|
After Width: | Height: | Size: 55 KiB |
|
After Width: | Height: | Size: 25 KiB |
|
After Width: | Height: | Size: 45 KiB |
|
After Width: | Height: | Size: 18 KiB |
|
After Width: | Height: | Size: 35 KiB |
|
After Width: | Height: | Size: 60 KiB |
|
After Width: | Height: | Size: 29 KiB |
|
After Width: | Height: | Size: 18 KiB |
|
After Width: | Height: | Size: 102 KiB |
|
After Width: | Height: | Size: 74 KiB |
|
After Width: | Height: | Size: 46 KiB |
|
After Width: | Height: | Size: 6.2 KiB |
|
After Width: | Height: | Size: 42 KiB |
|
After Width: | Height: | Size: 68 KiB |
|
After Width: | Height: | Size: 43 KiB |
|
After Width: | Height: | Size: 6.2 KiB |
|
After Width: | Height: | Size: 24 KiB |
Loading…
Reference in new issue