SpringBoot自动配置AutoConfiguration核心流程源码解析

SpringBoot自动配置

@SpringBootApplication包含@SpringBootConfiguration、@EnableAutoConfiguration、@ComponentScan、@ConfigurationPropertiesScan

SpringApplication.run启动流程中与自动配置相关流程：

1. SpringApplication启动

   org.springframework.boot.SpringApplication#run(java.lang.Class<?>, java.lang.String…)

2. 创建ApplicationContext

   org.springframework.boot.SpringApplication#createApplicationContext

3. 注册ConfigurationClassPostProcessor

   org.springframework.context.annotation.AnnotationConfigUtils#registerAnnotationConfigProcessors(org.springframework.beans.factory.support.BeanDefinitionRegistry)

4. refresh invoke BeanFactoryPostProcessor

   org.springframework.context.support.AbstractApplicationContext#invokeBeanFactoryPostProcessors

5. postProcess @Configuration

   org.springframework.context.annotation.ConfigurationClassPostProcessor#postProcessBeanDefinitionRegistry

6. process启动类SpringApplication配置类

   org.springframework.context.annotation.ConfigurationClassParser#doProcessConfigurationClass

7. ComponentSacn，默认扫描启动类包路径

   org.springframework.context.annotation.ComponentScanAnnotationParser#parse

8. process imports

   org.springframework.context.annotation.ConfigurationClassParser#processImports

9. 解析@SpringBootApplication注解的Imports，包括AutoConfigurationImportSelector
   -org.springframework.context.annotation.ConfigurationClassParser#processImports

   • org.springframework.boot.autoconfigure.AutoConfigurationPackages$Registrar
   • org.springframework.boot.autoconfigure.AutoConfigurationImportSelector
   • org.springframework.boot.context.properties.EnableConfigurationPropertiesRegistrar
   • org.springframework.boot.context.properties.ConfigurationPropertiesScanRegistrar

10. 处理ImportSelector
    org.springframework.context.annotation.ConfigurationClassParser.DeferredImportSelectorHandler#process

11. 加载EnableAutoConfiguration扩展点
    org.springframework.boot.autoconfigure.AutoConfigurationImportSelector.AutoConfigurationGroup#process