14.2 Locating the main application class
We generally recommend that you locate your main application class in a root package above other classes. The @EnableAutoConfiguration
annotation is often placed on your main class, and it implicitly defines a base “search package” for certain items. For example, if you are writing a JPA application, the package of the @EnableAutoConfiguration
annotated class will be used to search for @Entity
items.
Using a root package also allows the @ComponentScan
annotation to be used without needing to specify a basePackage
attribute. You can also use the @SpringBootApplication
annotation if your main class is in the root package.
Here is a typical layout:
com +- example +- myproject +- Application.java | +- domain | +- Customer.java | +- CustomerRepository.java | +- service | +- CustomerService.java | +- web +- CustomerController.java
The Application.java
file would declare the main
method, along with the basic @Configuration
.
package com.example.myproject; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; _@Configuration_ _@EnableAutoConfiguration_ _@ComponentScan_ public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }