A simple JavaConfig @configuration class. The equivalent xml is also added

AppConfig.java

@Configuration
public class AppConfig {
  @Bean
  public MyService myService() {
    return new MyServiceImpl();
  }
}

configuration.xml

<beans>
  <bean id="myService" class="com.acme.services.MyServiceImpl"/>
</beans>

StartUp.java

public static void main(String[] args) {
  ApplicationContext ctx = new AnnotationConfigApplicationContext(AppConfig.class);
  MyService myService = ctx.getBean(MyService.class);
  myService.doStuff();
}

StartUpWithRegistry.java

public static void main(String[] args) {
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
ctx.register(AppConfig.class, OtherConfig.class);
ctx.register(AdditionalConfig.class);
ctx.refresh();
MyService myService = ctx.getBean(MyService.class);
myService.doStuff();
}