Spring Boot启动时将示例数据插入数据库

Question

如果框架公开了一个钩子，以便在所有bean都被注入并且数据库准备就绪时进行操作，那么这也可以起作用。

Answer 1

您可以捕获ApplicationReadyEvent，然后插入演示数据，例如：

@Component
public class DemoData {

    @Autowired
    private final EntityRepository repo;

    @EventListener
    public void appReady(ApplicationReadyEvent event) {

        repo.save(new Entity(...));
    }
}

也可以实现CommandLineRunner或ApplicationRunner，以便在应用程序完全启动时加载演示数据：

@Component
public class DemoData implements CommandLineRunner {

    @Autowired
    private final EntityRepository repo;

    @Override
    public void run(String...args) throws Exception {

        repo.save(new Entity(...));
    }
}

@Component
public class DemoData implements ApplicationRunner {

    @Autowired
    private final EntityRepository repo;

    @Override
    public void run(ApplicationArguments args) throws Exception {

        repo.save(new Entity(...));
    }
}

甚至在应用程序（或其他“config”）类中像Bean一样实现它们：

@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    public CommandLineRunner demoData(EntityRepository repo) {
        return args -> { 

            repo.save(new Entity(...));
        }
    }
}