Spring 各种 Aware 接口回调注入

约定不等于承诺〃 2022-10-23 11:11 146阅读 0赞

Spring bean 实现了如下 Aware 接口，可以注入相关对象：

BeanFactoryAware,                //获取 IoC 容器 BeanFactory 的能力
    ApplicationContextAware,         //获取 Spring 应用上下文 ApplicationContext 对象的能力
    EnvironmentAware,                //获取 Environment 对象的能力
    ResourceLoaderAware,             //获取资源加载器对象 ResourceLoader 的能力
    BeanClassLoaderAware,            //获取加载当前 Bean Class 的 ClassLoader 的能力
    BeanNameAware,                   //获取当前 Bean 名称的能力
    MessageSourceAware,              //获取用于国际化 MessageSource 对象的能力
    ApplicationEventPublisherAware,  //获取事件发布对象 ApplicationEventPublisher 的能力
    EmbeddedValueResolverAware       //获取占位符处理对象 StringValueResolver 的能力

示例代码：

spring xml 配置

User 类

public class User implements
            BeanFactoryAware,                //获取 IoC 容器 BeanFactory 的能力
            ApplicationContextAware,         //获取 Spring 应用上下文 ApplicationContext 对象的能力
            EnvironmentAware,                //获取 Environment 对象的能力
            ResourceLoaderAware,             //获取资源加载器对象 ResourceLoader 的能力
            BeanClassLoaderAware,            //获取加载当前 Bean Class 的 ClassLoader 的能力
            BeanNameAware,                   //获取当前 Bean 名称的能力
            MessageSourceAware,              //获取用于国际化 MessageSource 对象的能力
            ApplicationEventPublisherAware,  //获取事件发布对象 ApplicationEventPublisher 的能力
            EmbeddedValueResolverAware       //获取占位符处理对象 StringValueResolver 的能力
    {
    
        private BeanFactory beanFactory;
        private ApplicationContext applicationContext;
        private Environment environment;
        private ResourceLoader resourceLoader;
        private ClassLoader beanClassLoader;
        private String beanName;
        private MessageSource messageSource;
        private ApplicationEventPublisher applicationEventPublisher;
        private StringValueResolver embeddedValueResolver;
    
        private Integer id;
    
        public Integer getId() {
            return id;
        }
    
        public void setId(Integer id) {
            this.id = id;
        }
    
        @Override
        public String toString() {
            return "User{" +
                    "beanFactory=" + beanFactory + '
    ' +
                    "applicationContext=" + applicationContext + '
    ' +
                    "environment=" + environment + '
    ' +
                    "resourceLoader=" + resourceLoader + '
    ' +
                    "beanClassLoader=" + beanClassLoader + '
    ' +
                    "beanName='" + beanName + ''' + '
    ' +
                    "messageSource=" + messageSource + '
    ' +
                    "applicationEventPublisher=" + applicationEventPublisher + '
    ' +
                    "embeddedValueResolver=" + embeddedValueResolver + '
    ' +
                    "id=" + id +
                    '}';
        }
    
        @Override
        public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
            this.beanFactory = beanFactory;
        }
        @Override
        public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
            this.applicationContext = applicationContext;
        }
        @Override
        public void setEnvironment(Environment environment) {
            this.environment = environment;
        }
        @Override
        public void setResourceLoader(ResourceLoader resourceLoader) {
            this.resourceLoader = resourceLoader;
        }
        @Override
        public void setBeanClassLoader(ClassLoader beanClassLoader) {
            this.beanClassLoader = beanClassLoader;
        }
        @Override
        public void setBeanName(String name) {
            this.beanName = name;
        }
        @Override
        public void setMessageSource(MessageSource messageSource) {
            this.messageSource = messageSource;
        }
        @Override
        public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
            this.applicationEventPublisher = applicationEventPublisher;
        }
        @Override
        public void setEmbeddedValueResolver(StringValueResolver stringValueResolver) {
            this.embeddedValueResolver = stringValueResolver;
        }
    }

测试代码

/**
     * 测试 Bean 通过接口方式回调注入系统内置 bean
     * @author ConstXiong
     */
    @Configuration
    public class Test {
    	
    	public static void main(String[] args) {
    		ApplicationContext context = new ClassPathXmlApplicationContext("/META-INF/spring-interface-callback-inject.xml");
    		User user = context.getBean("user1", User.class);
    		System.out.println(user);
    	}
    }

打印结果

User{beanFactory=org.springframework.beans.factory.support.DefaultListableBeanFactory@1a407d53: defining beans [user1]; root of factory hierarchy
    applicationContext=org.springframework.context.support.ClassPathXmlApplicationContext@6193b845, started on Thu Feb 04 14:21:00 CST 2021
    environment=StandardEnvironment {activeProfiles=[], defaultProfiles=[default], propertySources=[PropertiesPropertySource {name='systemProperties'}, SystemEnvironmentPropertySource {name='systemEnvironment'}]}
    resourceLoader=org.springframework.context.support.ClassPathXmlApplicationContext@6193b845, started on Thu Feb 04 14:21:00 CST 2021
    beanClassLoader=sun.misc.Launcher$AppClassLoader@18b4aac2
    beanName='user1'
    messageSource=org.springframework.context.support.ClassPathXmlApplicationContext@6193b845, started on Thu Feb 04 14:21:00 CST 2021
    applicationEventPublisher=org.springframework.context.support.ClassPathXmlApplicationContext@6193b845, started on Thu Feb 04 14:21:00 CST 2021
    embeddedValueResolver=org.springframework.beans.factory.config.EmbeddedValueResolver@520a3426
    id=1}

[完整代码：017-spring-interface-callback-inject][017-spring-interface-callback-inject]

--------------------

### 【Java学习资源】整理推荐 ###

*  [自定义 Bean 作用域][Bean]
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 *  [BeanFactory 与 FactoryBean 的区别][BeanFactory _ FactoryBean]
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--------------------

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[017-spring-interface-callback-inject]: https://github.com/ConstXiong/toy/tree/master/spring-study/017-spring-interface-callback-inject
[Bean]: https://www.javanav.com/val/3fdc7ac3bd034a5ab7040e23f37153fa.html
[Bean 1]: https://www.javanav.com/val/59101a7207864f4aa971e5c48b592c77.html
[maven _ tomcat _ jar _ web]: https://www.javanav.com/val/b1f4691bd6ba488a80e3bdfcefdec33c.html
[Spring]: https://www.javanav.com/val/a9569837e1bc4df9aeac0e6cbf96bf06.html
[Spring _ DependencyDescriptor]: https://www.javanav.com/val/152161d266a94fd38efb365a78d8f9a3.html
[Spring _ Aware]: https://www.javanav.com/val/089b3993c8bc4dec891ea677c104c5e4.html
[Spring Bean _ Exception]: https://www.javanav.com/val/2b31b7061b3342c0a67f8d7fc7373ed3.html
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[BeanDefinition]: https://www.javanav.com/val/e82279480ec24184bcaf723a50ef08b3.html
[Spring IoC]: https://www.javanav.com/val/d382c8380fc2480788a35a7e671b5e9b.html
[BeanFactory _ FactoryBean]: https://www.javanav.com/val/173e873a2c98499a8a08a13b4f88ae10.html
[BeanFactory _ ApplicationContext]: https://www.javanav.com/val/bbc2c9580b7045e583855925d5f1a50b.html
[Spring IoC 1]: https://www.javanav.com/val/a835e6c709ea439ebb21a80f1bf77926.html
[Spring IoC 2]: https://www.javanav.com/val/e377beac22644c2c85308079b239a0fd.html
[Spring bean]: https://www.javanav.com/val/7f8c2e1f24db46e79bc4b9b04f9ad715.html
[Spring-IoC]: https://www.javanav.com/val/a412668efda74412a13f6df9a6d2c714.html
[Spring 1]: https://www.javanav.com/val/6eac12a548ea40c68ff64b1af307563a.html
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[Redis]: https://www.javanav.com/interview/066c62b3af4d4827b2243a822c3084a9.html
[Dubbo]: https://www.javanav.com/interview/9a3e7a7740324757abaab953f7ebc455.html