无法在 Spring Boot 中自动装配对象列表 [英] Can't Autowire List of objects in Spring boot

问题描述

我正在 Spring Boot 中创建一个 REST 服务.我正在创建一个对象列表(List)作为配置类中的 bean 并尝试通过自动连接在服务类中使用，但我总是得到空列表，我尝试过构造函数注入以及但不工作.下面是代码，

I am creating a REST service in Spring boot. I am creating a list of objects(List<Record>) as bean in config class and trying to use in service class by auto wiring, but I am always getting empty list, I have tried in constructor injection as well but not working. Below is the code,

主应用

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

REST 控制器

@RestController
@RequestMapping("/v1")
public class RestController {

    @Autowired
    private Service service;

服务

 @Service
    public class ServiceImpl implements Service {
        @Autowired
    public ServiceImpl(List<Record> records) {
        System.out.println(records);  //------------------->getting empty list [null]
        data = new Data();
        customers = Arrays.asList("John", "James", "Calvin");
    }

配置类

@Configuration
public class AppConfig {
    
    @Bean
public List<Record> records(){
    List<Record> records = new ArrayList<Record>();
    records.add(new Record("d"));
    return records;
  }
}

我找不到我做错了什么，请指教.

I can't find what I am doing wrong please advise.

项目文件夹结构

推荐答案

以下代码对我有用:

public class Record {
    private final String s;

    public Record(String s) {
        this.s = s;
    }

    @Override
    public String toString() {
        return "Record{" +
                "s='" + s + '\'' +
                '}';
    }
}


@Service
public class RecordService {
    private final List<Record> recordList;

    public RecordService(List<Record> recordList) {
        this.recordList = recordList;
    }

}

@Configuration
public class MyConfiguration {
    @Bean
    public List<Record> recordList() {
        return Arrays.asList(new Record("a"), new Record("b"));
    }
}

一切都按预期注入(spring boot version 2.3.1.RELEASE)

Everything gets injected as expected (spring boot version 2.3.1.RELEASE)

从问题来看，您似乎做对了一切，我基本上只是确认 spring/spring boot 可以处理这样的情况.您使用哪个 spring boot/spring 版本?

From the question it looks like you did everything right and I basically just confirmed that spring / spring boot can deal with cases like this. Which spring boot/spring version do you use?

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