Springboot如何启动内置的tomcat（源码解析）？

传统项目为了启动，会放在tomcat下面，那么springboot为何不需要放在tomcat启动呢？？因为springboot有内置tomcat启动项目，这篇文章从源码分析springboot如何启动内置tomcat。
// Allows post-processing of the bean factory in context subclasses.
postProcessBeanFactory(beanFactory);

// Invoke factory processors registered as beans in the context.
invokeBeanFactoryPostProcessors(beanFactory);

// Register bean processors that intercept bean creation.
registerBeanPostProcessors(beanFactory);

// Initialize message

Springboot如何启动内置的tomcat（源码解析）？最先出现在Python成神之路。