Spring中Bean的生命周期

2019-11-14 14:58:36

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#准备工作
最近刚开始看韩顺平老师讲的SPRing基础，感觉听起来还是感觉比较好，也就教程中的案例做了实践，接下来记录一下，Spring中Bean的生命周期。
Spring的下载地址（我使用的是3.2.4）：http://repo.springsource.org/libs-release-local/org/springframework/spring/

①创建工程
首先，用IDE创建一个java工程，在工程目录下创建lib目录，复制需要引用的jar包并添加到ClassPath，因为我用的是Intellij，可能操作上与Eclipse有些不同。
②添加项目依赖Jar包
这个版本和教程中讲的2.5.5也有差异，主要是下载来的jar包中没有一个完整的包可以引用，只有一个个分开的jar包，这就使没有接触过Spring的我有些迷茫，
因为包很多，不知道哪些需要哪些不需要，查了一下资料，说是引用spring-core-3.2.4.RELEASE和spring-beans-3.2.4.RELEASE就够了，但是经过实践，还
需要引入spring-context-3.2.4.RELEASE、spring-expression-3.2.4.RELEASE和写日志的包commons-logging-1.1.1（需要单独下载）。
结论（需要引用的Jar包）：
spring-core-3.2.4.RELEASE | spring-beans-3.2.4.RELEASE | spring-context-3.2.4.RELEASE | spring-expression-3.2.4.RELEASE | commons-logging-1.1.1
③创建applicationContext.xml文件
到这一步又开始迷茫了，搜索一下找到复制过来，Intellij检查到没有使用的引用都是灰色的，所以就删除了未使用的，结果为：

<?xml version="1.0" encoding="utf-8"?><beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:schemaLocation="    http://www.springframework.org/schema/beans    http://www.springframework.org/schema/beans/spring-beans.xsd"></beans>

④创建类文件
User.java

 1 package com.spring.pojo; 2  3 import org.springframework.beans.BeansException; 4 import org.springframework.beans.factory.*; 5 import org.springframework.context.ApplicationContext; 6 import org.springframework.context.ApplicationContextAware; 7  8 public class User implements BeanNameAware, BeanFactoryAware, ApplicationContextAware, InitializingBean, DisposableBean { 9 10     private String name;11     // private String gender;12     // private Work service;13 14     public User() {15         System.out.println("①Constructor -> invoked");16     }17 18     public User(String name) {// , String gender, Work service) {19         this.name = name;20         // this.gender = gender;21         // this.service = service;22     }23 24     public String getName() {25         return name;26     }27 28     public void setName(String name) {29         System.out.println("①setName -> invoked");30         this.name = name;31     }32 33     /**34     public String getGender() {35         return gender;36     }37 38     public void setGender(String gender) {39         this.gender = gender;40     }41 42     public Work getService() {43         return service;44     }45 46     public void setService(Work service) {47         this.service = service;48     }49      */50 51     /**52      * init-method53      */54     public void initBean() {55         System.out.println("①initBean -> invoked");56     }57 58     public void show() {59         System.out.println("①" + this.name); // + "：" + this.gender + "/r/n" + service.getStatus());60     }61 62     @Override63     public void setBeanName(String s) {64         System.out.println("①" + s);65     }66 67     @Override68     public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {69         System.out.println("①" + applicationContext);70     }71 72     @Override73     public void setBeanFactory(BeanFactory beanFactory) throws BeansException {74         System.out.println("①" + beanFactory);75         Work workService = (Work) beanFactory.getBean("work");76         String status = workService.getStatus();77         System.out.println("②" + status);78     }79 80     @Override81     public void afterPropertiesSet() throws Exception {82         System.out.println("①afterPropertiesSet -> invoked");83     }84 85     @Override86     public void destroy() throws Exception {87         System.out.println("①DisposableBean's destroy -> invoked");88     }89 90     public void beforeDestroy() {91         System.out.println("①beforeDestroy -> invoked");92     }93 }

Work.java

 1 package com.spring.pojo; 2  3 import org.springframework.beans.BeansException; 4 import org.springframework.beans.factory.*; 5 import org.springframework.context.ApplicationContext; 6 import org.springframework.context.ApplicationContextAware; 7  8 public class Work implements BeanNameAware, BeanFactoryAware, ApplicationContextAware, InitializingBean, DisposableBean { 9 10     public String name;11     public String age;12 13     public Work() {14         System.out.println("②Constructor -> invoked");15     }16 17     public Work(String name, String age) {18         this.name = name;19         this.age = age;20     }21 22     public String getName() {23         return name;24     }25 26     public void setName(String name) {27         System.out.println("②setName -> invoked");28         this.name = name;29     }30 31     public String getAge() {32         return age;33     }34 35     public void setAge(String age) {36         this.age = age;37     }38 39     public String getStatus() {40         return this.name + "：" + this.age;41     }42 43     public void initMethod() {44         System.out.println("②initMethod -> invoked");45     }46 47     @Override48     public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {49         System.out.println("②" + applicationContext);50     }51 52     @Override53     public void setBeanFactory(BeanFactory beanFactory) throws BeansException {54         System.out.println("②" + beanFactory);55     }56 57     @Override58     public void setBeanName(String s) {59         System.out.println("②" + s);60     }61 62     @Override63     public void destroy() throws Exception {64         System.out.println("②destroy -> invoked");65     }66 67     @Override68     public void afterPropertiesSet() throws Exception {69         System.out.println("②afterPropertiesSet");70     }71 72     public void destroyMethod() {73         System.out.println("②destroyMethod -> invoked");74     }75 }

BeanProcessor.java

 1 package com.spring.pojo; 2  3 import org.springframework.beans.BeansException; 4 import org.springframework.beans.factory.config.BeanPostProcessor; 5  6 public class BeanProcessor implements BeanPostProcessor { 7  8     @Override 9     public Object postProcessBeforeInitialization(Object o, String s) throws BeansException {10         System.out.println("postProcessBeforeInitialization -> invoked");11         return o;12     }13 14     @Override15     public Object postProcessAfterInitialization(Object o, String s) throws BeansException {16         System.out.println("postProcessAfterInitialization -> invoked");17         return o;18     }19 }

UserTest.java

 1 package com.spring.pojo; 2  3 import com.spring.pojo.User; 4 import org.springframework.context.support.AbstractApplicationContext; 5 import org.springframework.context.support.ClassPathXmlApplicationContext; 6  7 public class UserTest { 8  9     public static void main(String[] args) {10         AbstractApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");11         User service = (User) context.getBean("user");12         service.show();13     }14 }

applicationContext.xml

<?xml version="1.0" encoding="utf-8"?><beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:schemaLocation="    http://www.springframework.org/schema/beans    http://www.springframework.org/schema/beans/spring-beans.xsd">    <bean id="user" class="com.spring.pojo.User"          scope="prototype"          init-method="initBean" destroy-method="beforeDestroy">        <property name="name" value="祁连山"/>        <!-- <property name="gender" value="男"/>        <property name="service" ref="workService"/> -->    </bean>    <bean id="work" class="com.spring.pojo.Work"        scope="prototype">        <property name="name" value="android开发"/>        <property name="age" value="三年"/>    </bean>    <bean id="beanProcessor" class="com.spring.pojo.BeanProcessor"/></beans>

⑤测试结果：
①Constructor -> invoked
①setName -> invoked
①user
①org.springframework.beans.factory.support.DefaultListableBeanFactory@3fcd000a: defining beans [user,work,beanProcessor]; root of factory hierarchy
②Constructor -> invoked
②setName -> invoked
②work
②org.springframework.beans.factory.support.DefaultListableBeanFactory@3fcd000a: defining beans [user,work,beanProcessor]; root of factory hierarchy
②org.springframework.context.support.ClassPathXmlApplicationContext@7c4633e7: startup date [Sun Nov 29 13:26:05 CST 2015]; root of context hierarchy
postProcessBeforeInitialization -> invoked
②afterPropertiesSet
postProcessAfterInitialization -> invoked
②android开发：三年
①org.springframework.context.support.ClassPathXmlApplicationContext@7c4633e7: startup date [Sun Nov 29 13:26:05 CST 2015]; root of context hierarchy
postProcessBeforeInitialization -> invoked
①afterPropertiesSet -> invoked
①initBean -> invoked
postProcessAfterInitialization -> invoked
①祁连山