Java中Spring扩展点详解

@Component
public class ContextRefreshedEventListener implements ApplicationListener<ContextRefreshedEvent> {
    @Override
    public void onApplicationEvent(ContextRefreshedEvent contextRefreshedEvent) {
        System.out.println("容器初始化完成,开始进行扩展！");
    }
}

/**
 * @author zhw
 * @description
 * @date 2021-09-29 15:28
 */
@Component
public class SmartInitializingSingletonTest implements SmartInitializingSingleton {
    @Override
    public void afterSingletonsInstantiated() {
        System.out.println("所有单例bean注册完成，开始扩展！");
    }
}

/**
 * @author zhw
 * @description
 * @date 2021-09-29 16:05
 */
public class ExtensionContext extends AnnotationConfigApplicationContext {
    public ExtensionContext(Class<MainConfig> mainConfigClass) {
        super(mainConfigClass);
    }
    @Override
    protected void initPropertySources() {
        //设置一些必须的环境变量
        getEnvironment().setRequiredProperties("appName");
    }
}

public class MyContextTest {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext annotationConfigApplicationContext = new ExtensionContext(MainConfig.class);
    }
}