详解Spring中Bean的作用域与生命周期

{"type":"doc","content":[{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​​​​​​摘要：在利用Spring进行IOC配置时，关于bean的配置和使用一直都是比较重要的一部分，同时如何合理的使用和创建bean对象，也是小伙伴们在学习和使用Spring时需要注意的部分，所以这一篇文章我就来和大家讲一下有关Spring中bean的作用域和其生命周期。","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"本文分享自华为云社区","attrs":{}},{"type":"link","attrs":{"href":"https://bbs.huaweicloud.com/blogs/284558?utm_source=infoq&utm_medium=bbs-ex&utm_campaign=other&utm_content=content","title":"","type":null},"content":[{"type":"text","text":"《详解Spring中Bean的作用域与生命周期》","attrs":{}}]},{"type":"text","text":"，原文作者：灰小猿。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在利用Spring进行IOC配置时，关于bean的配置和使用一直都是比较重要的一部分，同时如何合理的使用和创建bean对象，也是小伙伴们在学习和使用Spring时需要注意的部分，所以这一篇文章我就来和大家讲一下有关Spring中bean的作用域和其生命周期。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":1},"content":[{"type":"text","text":"一、Bean的作用域","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"首先我们来讲一下有关于bean的作用域","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"一般情况下，我们书写在IOC容器中的配置信息，会在我们的IOC容器运行时被创建，","attrs":{}},{"type":"text","text":"这就导致我们通过IOC容器获取到bean对象的时候，往往都是获取到了单实例的Bean对象","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"这样就意味着无论我们使用多少个getBean()方法，获取到的同一个JavaBean都是同一个对象，这就是单实例Bean，整个项目都会共享这一个bean对象。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"在Spring中，可以在元素的scope属性里设置bean的作用域，以决定这个bean是单实例的还是多实例的。","attrs":{}},{"type":"text","text":"Scope属性有四个参数，具体的使用可以看下图：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/09/097b69c4bd49c5b8fd89ccd2c93e1670.jpeg","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"1、单实例Bean声明","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"默认情况下，Spring只为每个在IOC容器里声明的bean创建唯一一个实例，整个IOC容器范围内都能共享该实例：所有后续的getBean()调用和bean引用都将返回这个唯一的bean实例。该作用域被称为singleton，","attrs":{}},{"type":"text","text":"它是所有bean的默认作用域。也就是单实例。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"为了验证这一说法，我们在IOC中创建一个单实例的bean，并且获取该bean对象进行对比：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"\n","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"测试获取到的单实例bean是否是同一个：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"@Test\npublic void test09() {\n // 单实例创建时创建的两个bean相等\n Book book03 = (Book)iocContext3.getBean(\"book02\");\n Book book04 = (Book)iocContext3.getBean(\"book02\");\n System.out.println(book03==book04);\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"得到的结果是true","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"2、多实例Bean声明","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"而既然存在单实例，那么就一定存在多实例。我们可以为bean对象的scope属性设置prototype参数，以表示该实例是多实例的，同时获取IOC容器中的多实例bean，再将获取到的多实例bean进行对比","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"\n","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"测试获取到的多实例bean是否是同一个：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"@Test\npublic void test09() {\n // 多实例创建时，创建的两个bean对象不相等\n Book book01 = (Book)iocContext3.getBean(\"book01\");\n Book book02 = (Book)iocContext3.getBean(\"book01\");\n System.out.println(book01==book02);\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"得到的结果是false","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"这就说明了，通过多实例创建的bean对象是各不相同的。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"在这里需要注意：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"同时关於单实例和多实例bean的创建也有不同，当bean的作用域为单例时，Spring会在IOC容器对象创建时就创建bean的对象实例。而当bean的作用域为prototype时，IOC容器在获取bean的实例时创建bean的实例对象。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":1},"content":[{"type":"text","text":"二、Bean的生命周期","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"1、bean的初始和销毁","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"其实我们在IOC中创建的每一个bean对象都是有其特定的生命周期的，在Spring的IOC容器中可以管理bean的生命周期，Spring允许在bean生命周期内特定的时间点执行指定的任务。如在bean初始化时执行的方法和bean被销毁时执行的方法。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"Spring IOC容器对bean的生命周期进行管理的过程可以分为六步：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"1.   通过构造器或工厂方法创建bean实例","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"2.   为bean的属性设置值和对其他bean的引用","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"3.   调用bean的初始化方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"4.   bean可以正常使用","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"5.   当容器关闭时，调用bean的销毁方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"那么关于bean的初始和销毁时执行的方法又该如何声明呢？","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"首先我们应该在bean类内部添加初始和销毁时执行的方法。如下面这个javabean：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"package com.spring.beans;\n\npublic class Book {\n\tprivate String bookName;\n\tprivate String author;\n\t/**\n\t * 初始化方法\n\t * */\n\tpublic void myInit() {\n\t\tSystem.out.println(\"book bean被创建\");\n\t}\n\t\n\t/**\n\t * 销毁时方法\n\t * */\n\tpublic void myDestory() {\n\t\tSystem.out.println(\"book bean被销毁\");\n\t}\n\t\n\tpublic String getBookName() {\n\t\treturn bookName;\n\t}\n\tpublic void setBookName(String bookName) {\n\t\tthis.bookName = bookName;\n\t}\n\tpublic String getAuthor() {\n\t\treturn author;\n\t}\n\tpublic void setAuthor(String author) {\n\t\tthis.author = author;\n\t}\n\t@Override\n\tpublic String toString() {\n\t\treturn \"Book [bookName=\" + bookName + \", author=\" + author + \"]\";\n\t}\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"这时我们在配置bean时，可以通过init-method和destroy-method 属性为bean指定初始化和销毁方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"\n","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"这样当我们在通过IOC容器创建和销毁bean对象时就会执行相应的方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"但是这里还是有一点需要注意：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"我们上面说了，单实例的bean和多实例的bean的创建时间是不同的，那么他们的初始方法和销毁方法的执行时间就稍稍有不同。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"单实例下 bean的生命周期","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"容器启动——>初始化方法——>（容器关闭）销毁方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"多实例下 bean的生命周期","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"容器启动——>调用bean——>初始化方法——>容器关闭（销毁方法不执行）","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"2、bean的后置处理器","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"什么是bean的后置处理器？bean后置处理器允许在调用","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"初始化方法前后","attrs":{}},{"type":"text","text":"对bean进行额外的处理","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"bean后置处理器对IOC容器里的所有bean实例逐一处理，而非单一实例。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"其典型应用是：检查bean属性的正确性或根据特定的标准更改bean的属性。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"bean后置处理器使用时需要实现接口：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"org.springframework.beans.factory.config.BeanPostProcessor。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在初始化方法被调用前后，Spring将把每个bean实例分别传递给上述接口的以下两个方法：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"postProcessBeforeInitialization(Object, String)调用前","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"postProcessAfterInitialization(Object, String)调用后","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"如下是一个实现在该接口的后置处理器：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"package com.spring.beans;\n\nimport org.springframework.beans.BeansException;\nimport org.springframework.beans.factory.config.BeanPostProcessor;\n\n/**\n * 测试bean的后置处理器\n * 在这里要注意一点是为了出现bean和beanName，而不是arg0、arg1，需要绑定相应的源码jar包\n * */\npublic class MyBeanPostProcessor implements BeanPostProcessor{\n\n\t/**\n\t * postProcessBeforeInitialization\n\t * 初始化方法执行前执行\n\t * Object bean\n\t * String beanName xml容器中定义的bean名称\n\t * */\n\t@Override\n\tpublic Object postProcessBeforeInitialization(Object bean, String beanName)\n\t\t\tthrows BeansException {\n\t\t// TODO Auto-generated method stub\n\t\tSystem.out.println(\"【\"+ beanName+\"】初始化方法执行前...\");\n\t\treturn bean;\n\t}\n\n\t/**\n\t * postProcessAfterInitialization\n\t * 初始化方法执行后执行\n\t * Object bean\n\t * String beanName xml容器中定义的bean名称\n\t * */\n\t@Override\n\tpublic Object postProcessAfterInitialization(Object bean, String beanName)\n\t\t\tthrows BeansException {\n\t\t// TODO Auto-generated method stub\n\t\tSystem.out.println(\"【\"+ beanName+\"】初始化方法执行后...\");\n\t\treturn bean;\n\t}\n\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"将该后置处理器加入到IOC容器中：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"\n","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"由于现在我们的bean对象是单实例的，所以容器运行时就会直接创建bean对象，同时也会执行该bean的后置处理器方法和初始化方法，在容器被销毁时又会执行销毁方法","attrs":{}},{"type":"text","text":"。我们测试如下：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"text"},"content":[{"type":"text","text":"//*************************bean生命周期*****************\n//\t由于ApplicationContext是一个顶层接口，里面没有销毁方法close，所以需要使用它的子接口进行接收\n\tConfigurableApplicationContext iocContext01 = new ClassPathXmlApplicationContext(\"ioc1.xml\");\n\t\n\t@Test\n\tpublic void test01() {\n\t\tiocContext01.getBean(\"book01\");\n\t\tiocContext01.close();\n\t}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"运行结果：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/79/79c843836012012f54ee791dd56f880e.jpeg","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/66/66bee5e3dd76751ffd900bfc32ab8946.jpeg","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"总结一下后置处理器的执行过程：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"1.    通过构造器或工厂方法","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"创建bean实例","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"2.    为bean的","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"属性设置值","attrs":{}},{"type":"text","text":"和对其他bean的引用","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"3.    将bean实例传递给bean后置处理器的","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"postProcessBeforeInitialization()","attrs":{}},{"type":"text","text":"方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"4.    调用bean的","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"初始化","attrs":{}},{"type":"text","text":"方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"5.    将bean实例传递给bean后置处理器的","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"postProcessAfterInitialization()","attrs":{}},{"type":"text","text":"方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"6.    bean可以使用了","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"7.    当容器关闭时调用bean的销毁方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"所以添加bean后置处理器后bean的生命周期为：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"容器启动——后置处理器的before...——>初始化方法——>后置处理器的after...———>（容器关闭）销毁方法","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"link","attrs":{"href":"https://bbs.huaweicloud.com/blogs?utm_source=infoq&utm_medium=bbs-ex&utm_campaign=other&utm_content=content","title":"","type":null},"content":[{"type":"text","text":"点击关注，第一时间了解华为云新鲜技术~","attrs":{}}]}]}]}