准备配置Bean

@Configuration
public class TestSpringApplication {static class Bean1 {}static class Bean2 {}static class Bean3 {}@Beanpublic Bean2 bean2() {return new Bean2();}@Beanpublic TomcatServletWebServerFactory tomcatServletWebServerFactory() {return new TomcatServletWebServerFactory();}}

准备配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"><bean id="bean1" class="com.you.meet.nice.test.web.springboot.TestSpringApplication.Bean1"/></beans>

测试加载BeanDefinition

测试推断应用类型

测试初始化器

测试主类推断

System.out.println("1. 从源中获取BeanDefinition");
// 配置类中获取
SpringApplication springApplication = new SpringApplication(TestSpringApplication.class);
// xml中获取
springApplication.setSources(CollUtil.newHashSet("classpath:b01.xml"
));System.out.println("2. 推断应用类型");
Method deduceFromClasspath = WebApplicationType.class.getDeclaredMethod("deduceFromClasspath");
deduceFromClasspath.setAccessible(true);
// 静态方法  不需要对象
System.out.println("\t应用类型:" + deduceFromClasspath.invoke(null));System.out.println("3. 添加初始化器");
springApplication.addInitializers(applicationContext -> {if (applicationContext instanceof GenericApplicationContext) {GenericApplicationContext gac = (GenericApplicationContext) applicationContext;// 这个初始化器被调用时  会注册一个beangac.registerBean("bean3", Bean3.class);}
});System.out.println("4. 添加监听器");
springApplication.addListeners(event -> {System.out.println("\t事件为:" + event.getClass());
});System.out.println("5. 主类推断");
Method deduceMainApplicationClass = SpringApplication.class.getDeclaredMethod("deduceMainApplicationClass");
deduceMainApplicationClass.setAccessible(true);
System.out.println("\t主类为:" + deduceMainApplicationClass.invoke(springApplication));ConfigurableApplicationContext applicationContext = springApplication.run(args);
// 创建ApplicationContext
// 调用初始化器对ApplicationContext做扩展
// ApplicationContext.refreshfor (String beanDefinitionName : applicationContext.getBeanDefinitionNames()) {System.out.println("beanName:" + beanDefinitionName + " 来源=>" + applicationContext.getBeanFactory().getBeanDefinition(beanDefinitionName).getResourceDescription());
}
applicationContext.close();