参考 https://blog.csdn.net/qq_25091649/article/details/88429512

 

情况一:在主类直接写controller接口,能够访问到

@SpringBootApplication
@RestController
public class DemoApplication {
	@RequestMapping("/index")
    public String index() {
      
        return "this is index!";
    }


	public static void main(String[] args) {
		//SpringApplication.run(DemoApplication.class, args);
		SpringApplication application = new SpringApplication(DemoApplication.class);
		application.setBannerMode(Mode.OFF);//关闭banner
		application.run(args);
	}

}


情况二:controller类单独写,且controller所在目录低于主类目录,此时也可以访问到

  

情况三:controller类单独写,且controller所在目录不在住类目录下,此时需要添加注解ComponentScan,里面写入要扫描的包

 

@ComponentScan(basePackages = {"com.xiao","com.example"})
@SpringBootApplication
public class DemoApplication {

	public static void main(String[] args) {
		//SpringApplication.run(DemoApplication.class, args);
		SpringApplication application = new SpringApplication(DemoApplication.class);
		application.setBannerMode(Mode.OFF);//关闭banner
		application.run(args);
	}

}

1、当启动类和controller在同一类中时,需要在该类上添加注解@Controller;

2、当启动类和controller分开时,启动目录高于controller目录,启动类上只有注解@SpringBootApplication;

3、当启动类和controller分开时,如果启动类在某个包下,需要在启动类中增加注解@ComponentScan,配置需要扫描的包名;

 

补充说明:对外的只有主类所在的模块,所以需要把其它模块添加到住类所在模块