Springboot project thread consumption queue injection reports error null pointer

background:

When calling Alibaba Cloud Privacy Protection, the receipt message of a call record is a consumer thread queue. Others told me this, because I didn't see where the thread was at all, so I treated it as an ordinary code and got the return value. Then insert into the database later

But I added everything that should be added here. The imported service kept reporting a null pointer. I was so angry that I

couldn't solve it so I went to the supervisor. The supervisor told me that this was a thread, and your injection would definitely not work. of. Then it disappeared. I was very happy. At least I had an idea and knew how to find a solution. However, after various Baidu and various attempts, it still didn’t work. Later, I went to find a colleague who had done multi-threading, and then the colleague gave me a tool to change the things that needed to be injected into my own.

@Service
public class MapperUtil {
    @Autowired
    public MoveCarService moveCarService;//改成自己的

    private static SimpleDateFormat df =
            new SimpleDateFormat("yyyy-MM-dd");//设置日期格式

    private int dueTime = 86400000;

    public static MapperUtil mapperUtil;  // 关键2

    public MapperUtil() {
    }

    // 关键3
    @PostConstruct
    public void init() {
        mapperUtil = this;
        mapperUtil.moveCarService = this.moveCarService;//改成上面对应的
    }
}

Then just call