EnableConfigurationProperties的實現原理

@EnableConfigurationProperties的實現原理

1、總結

通過spring生命週期的 beanPostprocessor接口將對象注入到容器中。

2、分析

2.1 EnableConfigurationProperties通過Import註解引入了配置屬性註冊類

@Import({EnableConfigurationPropertiesRegistrar.class})
public @interface EnableConfigurationProperties {
    String VALIDATOR_BEAN_NAME = "configurationPropertiesValidator";

    Class<?>[] value() default {};
}

2.2 bean定義登記類的實現引入了配置屬性bean註冊器

class EnableConfigurationPropertiesRegistrar implements ImportBeanDefinitionRegistrar {
  public void registerBeanDefinitions(AnnotationMetadata metadata, BeanDefinitionRegistry registry) {
        registerInfrastructureBeans(registry);
        registerMethodValidationExcludeFilter(registry);
        ConfigurationPropertiesBeanRegistrar beanRegistrar = new ConfigurationPropertiesBeanRegistrar(registry);
        this.getTypes(metadata).forEach(beanRegistrar::register);
    }
    
     static void registerInfrastructureBeans(BeanDefinitionRegistry registry) {
        ConfigurationPropertiesBindingPostProcessor.register(registry);
        BoundConfigurationProperties.register(registry);
    }
}   

2.3 配置屬性bean註冊器實現了BeanPosatProcessor接口

public class ConfigurationPropertiesBindingPostProcessor implements BeanPostProcessor, PriorityOrdered, ApplicationContextAware, InitializingBea