spring-boot runner.java

// loading load runner
@Bean
public ApplicationRunner runner(BalanceRepository balanceRepository) {
    return args -> {
        // ...
    };
}

@Component
public class DataLoader implements CommandLineRunner {
    @Override
    public void run(String... args) throws Exception {
        // ...
    }
}

@RequiredArgsConstructor
@Component
@Profile("post")
public class PostDataLoader implements CommandLineRunner {
    private final ObjectMapper objectMapper;
    private final PostRepository repository;

    @Override
    public void run(String... args) throws Exception {
        // src/main/resources/data/posts.json exists
        try (InputStream inputStream = this.getClass().getResourceAsStream("/data/posts.json")) {
            Posts response = objectMapper.readValue(inputStream, Posts.class);
            repository.saveAll(response.posts());
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        repository.findAll().forEach(System.out::println);
    }
}