// @SpringBootApplication is shorthand for:
@Configuration
@EnableAutoConfiguration
@ComponentScan
public class DemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

• @Configuration — this class can declare @Bean methods
• @EnableAutoConfiguration — turns on classpath-based auto-configuration
• @ComponentScan — scans this package and sub-packages for @Component beans