https://spring.io/guides#getting-started-guides
https://spring.io/guides/gs/rest-service/
keywords: pom.xml, @RestController (@Controller, @ResponseBody),
@GetMapping, @PostMapping <---- @RequestMapping
@SpringBootApplication (@Configuration, @EnableAutoConfiguration, @ComponentScan)
原文：https://www.cnblogs.com/zhangwanying/p/12395115.html