spring-boot ApplicationContextIn

ApplicationContextInitializer是在ConfigurableApplicationContext刷新之前初始化Spring ConfigurableApplicationContext的回调接口。当执行：ConfigurableApplicationContext.refresh()或SpringApplication.run()时生效。

实现方式

1）编写MyApplicationContextInitializer，实现ApplicationContextInitializer接口。

public class MyApplicationContextInitializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
    @Override
    public void initialize(ConfigurableApplicationContext configurableApplicationContext) {
        System.out.println("=======“);
    }
}

启动BlogApplication

@SpringBootApplication
public class BlogApplication {
    public static void main(String[] args) {
        SpringApplication springApplication = new SpringApplication(BlogApplication.class);
        //关键一步：将一个或多个initializer加入至spring容器中
        springApplication.addInitializers(new MyApplicationContextInitializer());
        springApplication.run(args).close();
    }
}

console result

2）在application.properties中以context.initializer.classes为key配置一个或多个自定义Initializer

application.properties
在BlogApplication中注释掉springApplication.addInitializers();

@SpringBootApplication
public class BlogApplication {
    public static void main(String[] args) {
        SpringApplication springApplication = new SpringApplication(BlogApplication.class);
        //springApplication.addInitializers(new MyApplicationContextInitializer());
        springApplication.run(args).close();
    }
}

console result

3）在META-INF/spring.factories中以org.springframework.context.ApplicationContextInitializer为key配置一个或多个initialier

spring.factories
执行结果和上图一样。

至此，springboot中的ApplicationContextInitializer实现与使用就结束啦，喜欢的读者可以持续关注我的springboot系列博客~