java - 如何在 Spring 中从文件连接 JSON 数据？

Question

我有一个简单的 Spring 应用程序。在那个应用程序中，我有 @Repository，它应该提供对包含我的数据的 JSON 文件的访问。

@Repository("jsonStorageUserRepository")
public class JsonUserRepository implements UserRepository {

    @Value("${users}")
    private List<User> users;

    @Override
    public User getByCursor(Cursor cursor) {
        return users.get(cursor.getId);
    }
}

我的 users.json 文件(存储)在 properties 文件夹中 -

[
    {
        "name": "Bill",
        "registered": true
    },
    {
        "name": "John",
        "registered": true
    }
]

还有我的 DTO 类 -

public class User implements Serializable {
    private boolean registered;
    private String name;

    public User(String name, boolean redistricted) {
        this.name = name;
        registered = redistricted;
    }
    // setters and getters were omitted
}

现在我有异常(exception):

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jsonStorageUserRepository': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private java.util.List com.springapp.mvc.repository.json.JsonUserRepository.users; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'users' in string value "${users}"

与这一行有关-

@Value("${users}")
private List<User> users;

是否可以从 JSON 连接转换后的实体列表？

Answer 1

读取 JSON 格式属性文件将不起作用。您需要编写自定义属性编辑器。看看那篇文章:

http://christopherhunt-software.blogspot.de/2010/04/spring-propertyeditor-for-json-map-and.html