{"id":10008042,"date":"2023-07-05T16:02:15","date_gmt":"2023-07-05T08:02:15","guid":{"rendered":"https:\/\/ityet.com\/?p=10008042"},"modified":"2023-07-05T16:02:15","modified_gmt":"2023-07-05T08:02:15","slug":"beanfactorypostprocessor-%e5%92%8c-beanpostprocessor-%e6%9c%89%e4%bb%80%e4%b9%88%e5%8c%ba%e5%88%ab%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10008042","title":{"rendered":"BeanFactoryPostProcessor \u548c BeanPostProcessor \u6709\u4ec0\u4e48\u533a\u522b\uff1f"},"content":{"rendered":"

\u7814\u7a76 Spring \u6e90\u7801\u7684\u5c0f\u4f19\u4f34\u53ef\u80fd\u4f1a\u53d1\u73b0\uff0cSpring \u6e90\u7801\u4e2d\u6709\u5f88\u591a\u540d\u79f0\u7279\u522b\u76f8\u8fd1\u7684 Bean\uff0c\u6211\u5c31\u4e0d\u6328\u4e2a\u4e3e\u4f8b\u4e86\uff0c\u4eca\u5929\u6211\u662f\u60f3\u548c\u5c0f\u4f19\u4f34\u4eec\u804a\u4e00\u804a Spring \u4e2d BeanFactoryPostProcessor \u548c BeanPostProcessor \u4e24\u4e2a\u5904\u7406\u5668\u7684\u533a\u522b\u3002<\/p>\n

\u6211\u5c06\u4ece\u4ee5\u4e0b\u51e0\u4e2a\u65b9\u9762\u6765\u548c\u5c0f\u4f19\u4f34\u4eec\u5206\u4eab\u3002<\/p>\n

1. \u533a\u522b<\/h2>\n

\u8fd9\u4e24\u4e2a\u63a5\u53e3\u8bf4\u767d\u4e86\u90fd\u662f Spring \u5728\u521d\u59cb\u5316 Bean \u65f6\u5bf9\u5916\u66b4\u9732\u7684\u6269\u5c55\u70b9\uff0c\u56e0\u4e3a Spring \u6846\u67b6\u63d0\u4f9b\u7684\u529f\u80fd\u4e0d\u4e00\u5b9a\u80fd\u591f\u6ee1\u8db3\u6211\u4eec\u6240\u6709\u7684\u9700\u6c42\uff0c\u6709\u7684\u65f6\u5019\u6211\u4eec\u9700\u8981\u5bf9\u5176\u8fdb\u884c\u6269\u5c55\uff0c\u90a3\u4e48\u8fd9\u4e24\u4e2a\u63a5\u53e3\u5c31\u662f\u7528\u6765\u505a\u6269\u5c55\u529f\u80fd\u7684\u3002<\/p>\n

\u5176\u5b9e\u4e0d\u7528\u770b\u6e90\u7801\uff0c\u5355\u7eaf\u4ece\u5b57\u9762\u4e0a\u770b\uff0c\u5927\u5bb6\u5e94\u8be5\u4e5f\u80fd\u7406\u89e3\u4e2a\u5dee\u4e0d\u591a\uff1a<\/p>\n

    \n
  1. BeanFactoryPostProcessor \u662f\u9488\u5bf9 BeanFactory \u7684\u5904\u7406\u5668\u3002<\/li>\n
  2. BeanPostProcessor \u5219\u662f\u9488\u5bf9 Bean \u7684\u5904\u7406\u5668\u3002<\/li>\n<\/ol>\n

    \u6211\u4eec\u5148\u6765\u770b\u4e0b BeanFactoryPostProcessor \u63a5\u53e3\uff1a<\/p>\n

    @FunctionalInterface\npublic interface BeanFactoryPostProcessor {\n    void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException;\n}<\/code><\/pre>\n
    \u53ef\u4ee5\u770b\u5230\uff0c\u8fd9\u91cc\u7684\u53c2\u6570\u5b9e\u9645\u4e0a\u5c31\u662f\u4e00\u4e2a BeanFactory\uff0c\u5728\u8fd9\u4e2a\u5730\u65b9\uff0c\u6211\u4eec\u53ef\u4ee5\u5bf9 BeanFactory \u8fdb\u884c\u4fee\u6539\uff0c\u91cd\u65b0\u8fdb\u884c\u5b9a\u5236\u3002\u4f8b\u5982\u53ef\u4ee5\u4fee\u6539\u4e00\u4e2a Bean \u7684\u4f5c\u7528\u57df\uff0c\u53ef\u4ee5\u4fee\u6539\u5c5e\u6027\u503c\u7b49\u3002<\/p>\n
    \u518d\u6765\u770b\u770b BeanPostProcessor \u63a5\u53e3\uff1a<\/p>\n
    public interface BeanPostProcessor {\n    @Nullable\n    default Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {\n        return bean;\n    }\n    @Nullable\n    default Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {\n        return bean;\n    }\n}<\/code><\/pre>\n
    \u53ef\u4ee5\u770b\u5230\uff0c\u8fd9\u91cc\u662f\u4e24\u4e2a\u65b9\u6cd5\uff0c\u8fd9\u4e24\u4e2a\u65b9\u6cd5\u90fd\u6709\u4e00\u4e2a bean \u5bf9\u8c61\uff0c\u8bf4\u660e\u8fd9\u91cc\u88ab\u89e6\u53d1\u7684\u65f6\u5019\uff0cSpring \u5df2\u7ecf\u5c06 Bean \u521d\u59cb\u5316\u4e86\uff0c\u7136\u540e\u624d\u4f1a\u89e6\u53d1\u8fd9\u91cc\u7684\u4e24\u4e2a\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u8fd9\u91cc\u5bf9\u5df2\u7ecf\u5230\u624b\u7684 Bean \u8fdb\u884c\u989d\u5916\u7684\u5904\u7406\u3002\u5176\u4e2d\uff1a<\/p>\n
      \n
    • postProcessBeforeInitialization\uff1a\u8fd9\u4e2a\u65b9\u6cd5\u5728 InitializingBean#afterPropertiesSet<\/code> \u548c init-method<\/code> \u65b9\u6cd5\u4e4b\u524d\u88ab\u89e6\u53d1\u3002<\/li>\n
    • postProcessAfterInitialization\uff1a\u8fd9\u4e2a\u65b9\u6cd5\u5728 InitializingBean#afterPropertiesSet<\/code> \u548c init-method<\/code> \u65b9\u6cd5\u4e4b\u540e\u88ab\u89e6\u53d1\u3002<\/li>\n<\/ul>\n
      \u603b\u7ed3\u4e00\u4e0b\uff1a<\/p>\n
      \u5728 Spring \u4e2d\uff0cBeanFactoryPostProcessor \u548c BeanPostProcessor \u662f\u4e24\u4e2a\u4e0d\u540c\u7684\u63a5\u53e3\uff0c\u5b83\u4eec\u5728 Bean \u7684\u751f\u547d\u5468\u671f\u4e2d\u626e\u6f14\u4e0d\u540c\u7684\u89d2\u8272\u3002<\/p>\n
        \n
      • BeanFactoryPostProcessor \u63a5\u53e3\u7528\u4e8e\u5728 Bean \u5de5\u5382\u5b9e\u4f8b\u5316 Bean \u4e4b\u524d\u5bf9 Bean \u7684\u5b9a\u4e49\u8fdb\u884c\u4fee\u6539\u3002\u5b83\u53ef\u4ee5\u8bfb\u53d6\u548c\u4fee\u6539 Bean \u7684\u5b9a\u4e49\u5143\u6570\u636e\uff0c\u4f8b\u5982\u4fee\u6539 Bean \u7684\u5c5e\u6027\u503c\u3001\u6dfb\u52a0\u989d\u5916\u7684\u914d\u7f6e\u4fe1\u606f\u7b49\u3002BeanFactoryPostProcessor \u5728 Bean \u5b9e\u4f8b\u5316\u4e4b\u524d\u6267\u884c\uff0c\u7528\u4e8e\u5bf9 Bean \u7684\u5b9a\u4e49\u8fdb\u884c\u9884\u5904\u7406\u3002<\/li>\n
      • BeanPostProcessor \u63a5\u53e3\u7528\u4e8e\u5728 Bean \u5b9e\u4f8b\u5316\u540e\u5bf9 Bean \u8fdb\u884c\u589e\u5f3a\u6216\u4fee\u6539\u3002\u5b83\u53ef\u4ee5\u5728 Bean \u7684\u521d\u59cb\u5316\u8fc7\u7a0b\u4e2d\u5bf9 Bean \u8fdb\u884c\u540e\u5904\u7406\uff0c\u4f8b\u5982\u5bf9 Bean \u8fdb\u884c\u4ee3\u7406\u3001\u6dfb\u52a0\u989d\u5916\u7684\u529f\u80fd\u7b49\u3002BeanPostProcessor \u5728 Bean \u5b9e\u4f8b\u5316\u5b8c\u6210\u540e\u6267\u884c\uff0c\u7528\u4e8e\u5bf9 Bean \u5b9e\u4f8b\u8fdb\u884c\u540e\u5904\u7406\u3002<\/li>\n<\/ul>\n
        \u4e00\u8a00\u4ee5\u853d\u4e4b\uff0cBeanFactoryPostProcessor \u4e3b\u8981\u7528\u4e8e\u4fee\u6539 Bean \u7684\u5b9a\u4e49\uff0c\u800c BeanPostProcessor \u4e3b\u8981\u7528\u4e8e\u589e\u5f3a\u6216\u4fee\u6539 Bean \u7684\u5b9e\u4f8b\u3002<\/p>\n
        2. \u4ee3\u7801\u5b9e\u8df5<\/h2>\n
        2.1 BeanFactoryPostProcessor<\/h3>\n
        BeanFactoryPostProcessor \u5728 Spring \u5bb9\u5668\u4e2d\u6709\u4e00\u4e2a\u975e\u5e38\u5178\u578b\u7684\u5e94\u7528\u3002<\/p>\n
        \u5f53\u6211\u4eec\u5728 Spring \u5bb9\u5668\u4e2d\u914d\u7f6e\u6570\u636e\u6e90\u7684\u65f6\u5019\uff0c\u4e00\u822c\u90fd\u662f\u6309\u7167\u4e0b\u9762\u8fd9\u6837\u7684\u65b9\u5f0f\u8fdb\u884c\u914d\u7f6e\u7684\u3002<\/p>\n
        \u9996\u5148\u521b\u5efa db.properties\uff0c\u5c06\u6570\u636e\u6e90\u5404\u79cd\u4fe1\u606f\u5199\u5165\u8fdb\u53bb\uff1a<\/p>\n
        db.username=root\ndb.password=123\ndb.url=jdbc:mysql:\/\/\/db01?serverTimezone=Asia\/Shanghai<\/code><\/pre>\n
        \u7136\u540e\u5728 Spring \u7684\u914d\u7f6e\u6587\u4ef6\u4e2d\uff0c\u9996\u5148\u628a\u8fd9\u4e2a\u914d\u7f6e\u6587\u4ef6\u52a0\u8f7d\u8fdb\u6765\uff0c\u7136\u540e\u5c31\u53ef\u4ee5\u5728 Spring Bean \u4e2d\u53bb\u4f7f\u7528\u5bf9\u5e94\u7684\u503c\u4e86\uff0c\u5982\u4e0b\uff1a<\/p>\n
        <context:property-placeholder location="classpath:db.properties"\/>\n<bean class="com.alibaba.druid.pool.DruidDataSource" id="dataSource">\n    <property name="username" value="${db.username}"\/>\n    <property name="password" value="${db.password}"\/>\n    <property name="url" value="${db.url}"\/>\n<\/bean><\/code><\/pre>\n
        \u4f46\u662f\u5927\u5bb6\u77e5\u9053\uff0c\u5bf9\u4e8e DruidDataSource \u6765\u8bf4\uff0c\u6beb\u65e0\u7591\u95ee\uff0c\u5b83\u8981\u7684\u662f\u5177\u4f53\u7684 username\u3001password \u4ee5\u53ca url\uff0c\u800c\u4e0a\u9762\u7684\u914d\u7f6e\u5f88\u660e\u663e\u4e2d\u95f4\u8fd8\u6709\u4e00\u4e2a\u8f6c\u6362\u7684\u8fc7\u7a0b\uff0c\u5373\u628a ${db.username}<\/code>\u3001${db.password}<\/code> \u4ee5\u53ca ${db.url}<\/code> \u8f6c\u4e3a\u5177\u4f53\u5bf9\u5e94\u7684\u503c\u3002\u90a3\u4e48\u8fd9\u4e2a\u8f6c\u6362\u662f\u600e\u4e48\u5b9e\u73b0\u7684\u5462\uff1f<\/p>\n
        \u8fd9\u5c31\u5f97\u5206\u6790 <context:property-placeholder location="classpath:db.properties"\/><\/code> \u914d\u7f6e\u4e86\uff0c\u5c0f\u4f19\u4f34\u4eec\u77e5\u9053\uff0c\u8fd9\u4e2a\u914d\u7f6e\u5b9e\u9645\u4e0a\u662f\u4e00\u4e2a\u7b80\u5316\u7684\u914d\u7f6e\uff0c\u70b9\u51fb\u53bb\u53ef\u4ee5\u770b\u5230\u771f\u6b63\u914d\u7f6e\u7684 Bean \u662f PropertySourcesPlaceholderConfigurer<\/code>\uff0c\u800c PropertySourcesPlaceholderConfigurer<\/code> \u6070\u597d\u5c31\u662f BeanFactoryPostProcessor<\/code> \u7684\u5b50\u7c7b\uff0c\u6211\u4eec\u6765\u770b\u4e0b\u8fd9\u91cc\u662f\u5982\u4f55\u91cd\u5199 postProcessBeanFactory \u65b9\u6cd5\u7684\uff1a<\/p>\n
        \u6e90\u7801\u6bd4\u8f83\u957f\uff0c\u677e\u54e5\u8fd9\u91cc\u628a\u4e00\u4e9b\u5173\u952e\u90e8\u5206\u5217\u51fa\u6765\u548c\u5c0f\u4f19\u4f34\u4eec\u5c55\u793a\uff1a<\/p>\n
        @Override\npublic void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {\n    if (this.propertySources == null) {\n        \/\/\u8fd9\u91cc\u4e3b\u8981\u662f\u5982\u679c\u6ca1\u6709\u52a0\u8f7d\u5230 properties \u6587\u4ef6\uff0c\u5c31\u4f1a\u5c1d\u8bd5\u4ece\u73af\u5883\u4e2d\u52a0\u8f7d\n    }\n    \/\/\u8fd9\u4e2a\u5c31\u662f\u5177\u4f53\u7684\u5c5e\u6027\u8f6c\u6362\u7684\u65b9\u6cd5\u4e86\n    processProperties(beanFactory, new PropertySourcesPropertyResolver(this.propertySources));\n    this.appliedPropertySources = this.propertySources;\n}\n\/**\n * \u8fd9\u4e2a\u5c5e\u6027\u8f6c\u6362\u65b9\u6cd5\u4e2d\uff0c\u5bf9\u914d\u7f6e\u6587\u4ef6\u53c8\u505a\u4e86\u4e00\u4e9b\u9884\u5904\u7406\uff0c\u6700\u540e\u8c03\u7528 doProcessProperties \u65b9\u6cd5\u5904\u7406\u5c5e\u6027\n *\/\nprotected void processProperties(ConfigurableListableBeanFactory beanFactoryToProcess,\n        final ConfigurablePropertyResolver propertyResolver) throws BeansException {\n    propertyResolver.setPlaceholderPrefix(this.placeholderPrefix);\n    propertyResolver.setPlaceholderSuffix(this.placeholderSuffix);\n    propertyResolver.setValueSeparator(this.valueSeparator);\n    StringValueResolver valueResolver = strVal -> {\n        String resolved = (this.ignoreUnresolvablePlaceholders ?\n                propertyResolver.resolvePlaceholders(strVal) :\n                propertyResolver.resolveRequiredPlaceholders(strVal));\n        if (this.trimValues) {\n            resolved = resolved.trim();\n        }\n        return (resolved.equals(this.nullValue) ? null : resolved);\n    };\n    doProcessProperties(beanFactoryToProcess, valueResolver);\n}\nprotected void doProcessProperties(ConfigurableListableBeanFactory beanFactoryToProcess,\n        StringValueResolver valueResolver) {\n    BeanDefinitionVisitor visitor = new BeanDefinitionVisitor(valueResolver);\n    String[] beanNames = beanFactoryToProcess.getBeanDefinitionNames();\n    for (String curName : beanNames) {\n        \/\/ Check that we're not parsing our own bean definition,\n        \/\/ to avoid failing on unresolvable placeholders in properties file locations.\n        if (!(curName.equals(this.beanName) && beanFactoryToProcess.equals(this.beanFactory))) {\n            BeanDefinition bd = beanFactoryToProcess.getBeanDefinition(curName);\n            try {\n                visitor.visitBeanDefinition(bd);\n            }\n            catch (Exception ex) {\n                throw new BeanDefinitionStoreException(bd.getResourceDescription(), curName, ex.getMessage(), ex);\n            }\n        }\n    }\n    \/\/ New in Spring 2.5: resolve placeholders in alias target names and aliases as well.\n    beanFactoryToProcess.resolveAliases(valueResolver);\n    \/\/ New in Spring 3.0: resolve placeholders in embedded values such as annotation attributes.\n    beanFactoryToProcess.addEmbeddedValueResolver(valueResolver);\n}<\/code><\/pre>\n
        \u4e0a\u9762\u7b2c\u4e09\u4e2a doProcessProperties \u65b9\u6cd5\u6211\u8981\u7a0d\u5fae\u548c\u5c0f\u4f19\u4f34\u4eec\u8bf4\u4e24\u53e5\uff1a<\/p>\n
        \u4f7f\u7528 PropertySourcesPlaceholderConfigurer \u5bf9\u914d\u7f6e\u4e2d\u7684\u5360\u4f4d\u7b26\u8fdb\u884c\u5904\u7406\uff0c\u867d\u7136\u6211\u4eec\u53ea\u662f\u5728 DruidDataSource \u4e2d\u7528\u5230\u4e86\u76f8\u5173\u53d8\u91cf\uff0c\u4f46\u662f\u7cfb\u7edf\u5728\u5904\u7406\u7684\u65f6\u5019\uff0c\u9664\u4e86\u5f53\u524d\u8fd9\u4e2a\u914d\u7f6e\u7c7b\u4e4b\u5916\uff0c\u5176\u4ed6\u7684 Bean \u90fd\u8981\u5904\u7406\uff08\u56e0\u4e3a\u4f60\u53ef\u4ee5\u5728\u4efb\u610f Bean \u4e2d\u6ce8\u5165\u90a3\u4e09\u4e2a\u53d8\u91cf\uff09\u3002<\/p>\n
        \u8fd9\u5c31\u662f BeanFactoryPostProcessor \u4e00\u4e2a\u7ecf\u5178\u5b9e\u8df5\uff0c\u5373\u5728 Bean \u521d\u59cb\u5316\u4e4b\u524d\uff0c\u628a Bean \u5b9a\u4e49\u65f6\u5019\u7684\u4e00\u4e9b\u5360\u4f4d\u7b26\u7ed9\u6539\u8fc7\u6765\u3002<\/p>\n
        2.2 \u7167\u732b\u753b\u864e<\/h3>\n
        \u4e0a\u9762\u7684\u6e90\u7801\u770b\u5b8c\u4e86\uff0c\u5982\u679c\u5c0f\u4f19\u4f34\u4eec\u8fd8\u89c9\u5f97\u4e0d\u8fc7\u763e\uff0c\u6211\u4eec\u81ea\u5df1\u4e5f\u6765\u5199\u4e00\u4e2a\u8bd5\u8bd5\u3002<\/p>\n
        \u6211\u81ea\u5df1\u7684\u9700\u6c42\u662f\u8fd9\u6837\uff0c\u5047\u8bbe\u6211\u914d\u7f6e Bean \u7684\u65f6\u5019\uff0c\u6309\u7167\u4e0b\u9762\u8fd9\u79cd\u65b9\u5f0f\u6765\u914d\u7f6e\uff1a<\/p>\n
        <bean class="org.javaboy.bean.User">\n    <property name="username" value="^username"\/>\n<\/bean><\/code><\/pre>\n
        \u8fd9\u91cc\u7684 ^username<\/code> \u662f\u6211\u81ea\u5b9a\u4e49\u7684\u4e00\u4e2a\u7279\u6b8a\u7684\u5360\u4f4d\u7b26\uff0c\u8fd9\u4e2a\u5360\u4f4d\u7b26\u8868\u793a javaboy\uff0c\u6211\u5e0c\u671b\u6700\u7ec8\u4ece Spring \u5bb9\u5668\u4e2d\u62ff\u5230\u7684 User Bean \u7684 username \u5c5e\u6027\u503c\u662f javaboy\u3002<\/p>\n
        \u4e3a\u4e86\u5b9e\u73b0\u8fd9\u4e2a\u9700\u6c42\uff0c\u6211\u53ef\u4ee5\u81ea\u5b9a\u4e49\u4e00\u4e2a BeanFactoryPostProcessor\uff0c\u5982\u4e0b\uff1a<\/p>\n
        public class MyPropBeanFactoryPostProcessor implements BeanFactoryPostProcessor {\n    @Override\n    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {\n        String[] beanDefinitionNames = beanFactory.getBeanDefinitionNames();\n        for (String beanDefinitionName : beanDefinitionNames) {\n            BeanDefinition beanDefinition = beanFactory.getBeanDefinition(beanDefinitionName);\n            BeanDefinitionVisitor beanDefinitionVisitor = new BeanDefinitionVisitor(strVal -> {\n                if ("^username".equals(strVal)) {\n                    return "javaboy666";\n                }\n                return strVal;\n            });\n            beanDefinitionVisitor.visitBeanDefinition(beanDefinition);\n        }\n    }\n}<\/code><\/pre>\n
        \u8fd9\u4e2a Bean \u57fa\u672c\u4e0a\u662f\u7167\u7740\u524d\u9762 2.1 \u5c0f\u8282\u7684 Bean \u6765\u5199\u7684\u3002\u6211\u8ddf\u5927\u5bb6\u6765\u5927\u81f4\u8bf4\u4e00\u4e0b\u6211\u7684\u903b\u8f91\uff1a<\/p>\n
          \n
        1. \u9996\u5148\u83b7\u53d6\u5230\u6240\u6709\u7684 Bean \u5b9a\u4e49\u5bf9\u8c61\uff0c\u7136\u540e\u8fdb\u884c\u904d\u5386\u3002<\/li>\n
        2. \u904d\u5386\u7684\u65f6\u5019\u521b\u5efa\u4e00\u4e2a BeanDefinitionVisitor \u5bf9\u8c61\uff0c\u8fd9\u4e2a\u5bf9\u8c61\u9700\u8981\u4e00\u4e2a\u5b57\u7b26\u89e3\u6790\u5668\uff0c\u4e5f\u5c31\u662f lambda \u8868\u8fbe\u5f0f\u90a3\u4e00\u6bb5\uff0c\u6211\u8fd9\u91cc\u5c31\u662f\u8bf4\uff0c\u5982\u679c\u4f20\u8fdb\u6765\u7684\u5b57\u7b26\u4e32\u662f ^username<\/code>\uff0c\u90a3\u4e48\u6211\u5c31\u8fd4\u56de javaboy\uff0c\u5982\u679c\u4f20\u8fdb\u6765\u5176\u4ed6\u503c\uff0c\u90a3\u6211\u539f\u5c01\u4e0d\u52a8\uff0c\u4e0d\u505a\u4fee\u6539\u3002<\/li>\n
        3. \u6700\u540e\u8c03\u7528 visitBeanDefinition \u65b9\u6cd5\u53bb\u91cd\u65b0\u8bbe\u7f6e\u4e00\u4e0b Bean \u7684\u5b9a\u4e49\u3002<\/li>\n<\/ol>\n
          \u4e0a\u9762\u8fd9\u51e0\u884c\u4ee3\u7801\u57fa\u672c\u4e0a\u5c31\u662f\u7167\u7740 2.1 \u5c0f\u8282\u6572\u7684\uff0c\u6700\u540e\uff0c\u6211\u4eec\u628a MyPropBeanFactoryPostProcessor \u6ce8\u518c\u5230 Spring \u5bb9\u5668\u4e2d\u5c31\u884c\u4e86\uff1a<\/p>\n
          <bean class="org.javaboy.bean.User">\n    <property name="username" value="^username"\/>\n<\/bean>\n<bean class="org.javaboy.bean.MyPropBeanFactoryPostProcessor"\/><\/code><\/pre>\n
          \u770b\u4e0b\u6267\u884c\u6548\u679c\uff1a<\/p>\n
          \"\"<\/p>\n
          2.3 BeanPostProcessor<\/h3>\n
          BeanPostProcessor \u4e3b\u8981\u662f\u5bf9\u4e00\u4e2a\u5df2\u7ecf\u521d\u59cb\u5316\u7684 Bean \u505a\u4e00\u4e9b\u989d\u5916\u7684\u914d\u7f6e\uff0c\u8fd9\u4e2a\u63a5\u53e3\u4e2d\u5305\u542b\u4e24\u4e2a\u65b9\u6cd5\uff0c\u6267\u884c\u65f6\u95f4\u5982\u4e0b\u56fe\uff1a<\/p>\n
          \"\"<\/p>\n
          \u6211\u5199\u4e00\u4e2a\u7b80\u5355\u4f8b\u5b50\u6211\u4eec\u6765\u9a8c\u8bc1\u4e0b\uff1a<\/p>\n
          public class UserService implements InitializingBean {\n\n    public UserService() {\n        System.out.println("UserService>Constructor");\n    }\n\n    public void init() {\n        System.out.println("UserService>init");\n    }\n    @Override\n    public void afterPropertiesSet() throws Exception {\n        System.out.println("UserService>afterPropertiesSet");\n    }\n}<\/code><\/pre>\n
          \u518d\u5f00\u53d1\u4e00\u4e2a BeanPostProcessor\uff1a<\/p>\n
          public class MyBeanPostProcessor implements BeanPostProcessor {\n    @Override\n    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {\n        System.out.println("postProcessBeforeInitialization:beanName"+beanName+";beanClass:"+bean.getClass());\n        return BeanPostProcessor.super.postProcessBeforeInitialization(bean, beanName);\n    }\n\n    @Override\n    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {\n        System.out.println("postProcessAfterInitialization:beanName"+beanName+";beanClass:"+bean.getClass());\n        return BeanPostProcessor.super.postProcessAfterInitialization(bean, beanName);\n    }\n}<\/code><\/pre>\n
          \u7136\u540e\u6211\u4eec\u5c06\u8fd9\u4e24\u4e2a Bean \u90fd\u6ce8\u518c\u5230 Spring \u5bb9\u5668\u4e2d\uff1a<\/p>\n
          <bean class="org.javaboy.bean.MyBeanPostProcessor"\/>\n<bean class="org.javaboy.bean.UserService" id="us" init-method="init">\n<\/bean><\/code><\/pre>\n
          \u6700\u540e\u542f\u52a8\u5bb9\u5668\uff0c\u6765\u770b\u4e0b\u63a7\u5236\u53f0\u6253\u5370\u7684\u5185\u5bb9\uff1a<\/p>\n
          \"\"<\/p>\n
          \u53ef\u4ee5\u770b\u5230\uff0c\u8ddf\u6211\u4eec\u6240\u9884\u60f3\u7684\u662f\u4e00\u6837\u7684\u3002\u5728 MyBeanPostProcessor \u4e2d\uff0c\u7b2c\u4e00\u4e2a\u53c2\u6570\u5176\u5b9e\u5c31\u662f\u5df2\u7ecf\u521d\u59cb\u5316\u7684 Bean \u4e86\uff0c\u5982\u679c\u60f3\u5728\u8fd9\u91cc\u9488\u5bf9 Bean \u505a\u4efb\u4f55\u4fee\u6539\u90fd\u662f\u53ef\u4ee5\u7684\u3002<\/p>\n
          2.4 \u5178\u578b\u5e94\u7528<\/h3>\n
          BeanPostProcessor \u5176\u5b9e\u6709\u5f88\u591a\u7ecf\u5178\u7684\u5e94\u7528\uff0c\u6211\u5728\u5199\u6587\u7ae0\u7684\u65f6\u5019\uff0c\u60f3\u5230\u4e00\u4e2a\u5730\u65b9\uff0c\u5c31\u662f\u6211\u4eec\u5728 SpringMVC \u4e2d\u505a\u6570\u636e\u9a8c\u8bc1\u7684\u65f6\u5019\uff0c\u5f80\u5f80\u53ea\u9700\u8981\u52a0\u51e0\u4e2a\u6ce8\u89e3\u5c31\u53ef\u4ee5\u4e86\uff08\u5bf9\u6b64\u4e0d\u719f\u6089\u7684\u5c0f\u4f19\u4f34\u53ef\u4ee5\u5728\u516c\u4f17\u53f7\u540e\u53f0\u56de\u590d ssm \u6709\u677e\u54e5\u5f55\u5236\u7684 ssm \u5165\u95e8\u89c6\u9891\uff09\uff0c\u90a3\u4e48\u8fd9\u4e2a\u6ce8\u89e3\u662f\u5728\u54ea\u91cc\u8fdb\u884c\u7684\u6821\u9a8c\u7684\u5462\uff1f\u5c31\u662f BeanPostProcessor\uff0c\u6211\u4eec\u6765\u770b\u4e00\u773c\u6e90\u7801\uff1a<\/p>\n
          public class BeanValidationPostProcessor implements BeanPostProcessor, InitializingBean {\n\n    @Nullable\n    private Validator validator;\n\n    private boolean afterInitialization = false;\n\n    public void setAfterInitialization(boolean afterInitialization) {\n        this.afterInitialization = afterInitialization;\n    }\n\n    @Override\n    public void afterPropertiesSet() {\n        if (this.validator == null) {\n            this.validator = Validation.buildDefaultValidatorFactory().getValidator();\n        }\n    }\n    @Override\n    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {\n        if (!this.afterInitialization) {\n            doValidate(bean);\n        }\n        return bean;\n    }\n    @Override\n    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {\n        if (this.afterInitialization) {\n            doValidate(bean);\n        }\n        return bean;\n    }\n    \/**\n     * Perform validation of the given bean.\n     * @param bean the bean instance to validate\n     * @see jakarta.validation.Validator#validate\n     *\/\n    protected void doValidate(Object bean) {\n        \/\/...\n    }\n\n}<\/code><\/pre>\n
          \u8fd9\u6bb5\u4ee3\u7801\u5176\u5b9e\u5f88\u597d\u61c2\uff0c\u53ef\u4ee5\u770b\u5230\uff0c\u6211\u4eec\u53ef\u4ee5\u63a7\u5236\u662f\u5728\u5177\u4f53\u662f\u5728 postProcessBeforeInitialization \u8fd8\u662f postProcessAfterInitialization \u65b9\u6cd5\u4e2d\u8fdb\u884c\u6570\u636e\u6821\u9a8c\u3002<\/p>\n
          \u597d\u4e86\uff0c\u73b0\u5728\u5c0f\u4f19\u4f34\u4eec\u5e94\u8be5\u641e\u61c2 BeanFactoryPostProcessor \u548c BeanPostProcessor \u7684\u533a\u522b\u4e86\u5427\uff1f<\/p>\n
          3. \u5c0f\u7ed3<\/h2>\n
          \u6211\u518d\u628a\u524d\u6587\u7684\u5c0f\u7ed3\u5185\u5bb9\u62ff\u8fc7\u6765\uff0c\u5c0f\u4f19\u4f34\u4eec\u73b0\u5728\u770b\u662f\u4e0d\u662f\u66f4\u6e05\u6670\u4e86\uff1f<\/p>\n
          \u5728 Spring \u4e2d\uff0cBeanFactoryPostProcessor \u548c BeanPostProcessor \u662f\u4e24\u4e2a\u4e0d\u540c\u7684\u63a5\u53e3\uff0c\u5b83\u4eec\u5728 Bean \u7684\u751f\u547d\u5468\u671f\u4e2d\u626e\u6f14\u4e0d\u540c\u7684\u89d2\u8272\u3002<\/p>\n