Question

我正在创建pojo类并存储application.properties变量，但是我得到的是空值

注意：需要从我的Abstract类访问env

POJO类

package mynt.xyz.c4.pushnotif.config;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;

@Configuration("notificationEnvironment")
@ConfigurationProperties(prefix = "app.notif")
public class NotificationEnvironment {
    private String key;
    private String url;

    public String getKey() {
        return key;
    }

    public void setKey(String key) {
        this.key = key;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

}

使用@autowired初始化类

public abstract class NotificationBase {

    @Autowired
    NotificationEnvironment notificationEnvironment;

    public void getEnv(){
    system.out.println(notificationEnvironment.getKey()); // null value
    }
}

扩展到我的NotificationBaseClass的具体类

@Component
@Qualifier("androidNotification")
public class AndroidNotification extends NotificationBase implements Notification {

    public AndroidNotification(String message, String title, String datalink, List<String> instanceIds) {
        super(message, title, datalink, instanceIds);
    }

    AndroidNotification(){
        super();
    }

    @Override
    public void send() {
        this.getEnv();
    }
}

application.properties

app.notif.key=jkashdkjashd
app.notif.url=https/some.url

Answer 1

您可以从 @Configuration 个课程中auto wire @Configuration个课程

@Configuration类可以使用@Autowired引用任何其他@Configuration类的实例。之所以有效，是因为@Configuration类本身被实例化并作为单独的Spring Bean管理。

Answer 2

使您的类@Component并在@ConfigurationProperties中添加前缀值，如下所示。这对我有用，希望对您也有用。

@Component
@ConfigurationProperties(prefix = "app.notif")
public class NotificationEnvironment {
    private String key;
    private String url;

    public String getKey() {
        return key;
    }

    public void setKey(String key) {
        this.key = key;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

}

您可以使用以下属性：

@Component
public class NotificationBase {

    private static NotificationEnvironment notificationEnvironment;

    @Autowired
    public NotificationBase(NotificationEnvironment notificationEnvironment){
        this.notificationEnvironment = notificationEnvironment;
    }

    public static void getEnv(){
        System.out.println(notificationEnvironment.getKey()); // null value
    }

}

Answer 3

这是OP作者提到的具体的类定义之一。

public abstract class NotificationBase {

    NotificationEnvironment notificationEnvironment;

    public NotificationBase(NotificationEnvironment notificationEnvironment) {
        this.notificationEnvironment = notificationEnvironment;
    }

    public void getEnv(){
        System.out.println(notificationEnvironment.getKey());
    }
}

更新了NotificationBase如下

@RestController
public class ArticleCommentController {

    @Autowired
    ConcreteNotification concreteNotification;


    @RequestMapping(value = "/health_check", method = RequestMethod.GET)
    public void getDemo() {
        concreteNotification.getEnv();
    }
}

我用来获取配置值的控制器类

Column

输出：

jkashdkjashd

从@configuration获取空值

3 个答案: