If Spring Boot calls the address you mapped to the controller and gets a 404, 

 

You can handle this in one of two ways

 

 

1) You can add a ComponentScan annotation to directly specify which packages to scan.

 

@SpringBootApplication

@ComponentScan(basePackages = {"com.example", "com.test"})

 

 

2) Place the controller under the Spring Boot main application's package.

 

If the Spring Boot main application's package is com.example.demo,

you would set the controller's package to be subordinate to com.example.demo.