@Inject 注入还是报空指针

Posted 2020-10-12 疯子加天才

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@IocBean
@Service("userManagerService")
public class UserManagerServiceImpl implements UserManagerService{
@Inject private UserMastManagerBiz userMastManagerBiz;
public UserRegisterServiceResponseDTO addUser(
UserRegisterServiceRequestDTO requestDTO){
UserRegisterServiceResponseDTO responseDTO
= userMastManagerBiz.registerUserAccount(requestDTO);
return responseDTO;
}
}

结果 userMastManagerBiz 报空指针

wendal

1楼•572天前

可能性：

在js里面配置这个bean

对象是手动new的

子寒磊(ds25)

2楼•572天前

@wendal 你的意思是UserMastManagerBiz 是手动new的，不是注入的吗？

wendal

3楼•572天前

不是

wendal

4楼•572天前

要看 UserManagerServiceImpl 是怎么生成的, 问题是出在UserManagerServiceImpl 上

检查ioc的js文件, 看看有无重复声明, 同一个bean, 要么用js,要么用注解, 只能有一种生效
要是这个类的对象是直接new出来的,那就肯定没有"注入"这一服务了.

子寒磊(ds25)

5楼•572天前

@wendal /*
* 本配置文件声明了整个应用的数据库连接部分。
*/
var ioc = {

dataSource : {
    type : "com.alibaba.druid.pool.DruidDataSource",
    fields : {
       driverClass : "oracle.jdbc.driver.OracleDriver",
       jdbcUrl : "jdbc:oracle:thin:@:1521:orcl",
       user : "",
       password : ""
    } 
},
dao : {
    type : "org.nutz.dao.impl.NutDao",
    args : [ {
       refer : "dataSource"
    } ]
}

};

我在js中没有声明bean，全都是以注入方式写的

这是我的nutz日志：
ALL Nutz Log via Log4jLogAdapter
[INFO ] [2016/04/02 11:04:59] SEE org.nutz.log.Logs - Nutz is licensed under the Apache License, Version 2.0 .
Report bugs : https://github.com/nutzam/nutz/issues
[INFO ] [2016/04/02 11:04:59] SEE org.nutz.mvc.NutFilter - NutFilter[nutz] starting ...
[INFO ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - Nutz Version : 1.b.51
[INFO ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - Nutz.Mvc[nutz] is initializing ...
[INFO ] [2016/04/02 11:05:02] SEE org.nutz.ioc.loader.annotation.AnnotationIocLoader - Scan complete ! Found 13 classes in 1 base-packages!
beans = ["customerCodeBiz", "home", "baseDao", "userMastManagerBiz", "complexDatabase", "mongoDao", "simpleDababase", "memcached", "baseBiz", "commonMongoService", "errorMessageContent", "userManagerServiceImpl", "baseMongo"] [INFO ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - Build URL mapping by org.nutz.mvc.impl.UrlMappingImpl ...
[WARN ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - None module classes found!!!
[WARN ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - None @At found in any modules class!!
[INFO ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - Setup application...
[INFO ] [2016/04/02 11:05:02] SEE org.nutz.mvc.impl.NutLoading - Nutz.Mvc[nutz] is up in 528ms

这里是生成了这个userManagerServiceImpl 这个对象吧

wendal

6楼•572天前

@ds25 只是生成了定义,对象还没生成.

使用UserManagerServiceImpl 的代码贴一下, 估计是new UserManagerServiceImpl ()的, 而非从ioc容器拿.

子寒磊(ds25)

7楼•572天前

@wendal

@Controller
@RequestMapping("/home")
public class Home {

private Logger logger = Logger.getLogger(Home.class);

@Inject
private UserManagerServiceImpl  userManagerService;

/**
 * 个人日记-注册页面
 * 
 * @return
 * @Description:
 */
@RequestMapping(value = "/{site}/register" , method = RequestMethod.GET)
public ModelAndView register(HttpServletRequest request,
       HttpServletResponse response) {
    logger.info("进入注册页   register START");
    ModelAndView mav = new ModelAndView();
    mav.setViewName("homePage/registerPage");
    logger.info("进入注册页   register End");
    return mav;
}

/**
 * 个人日记-正在注册
 * 
 * @return
 * @Description:
 */
@SuppressWarnings("unused")
@RequestMapping(value = "/{site}/registering" , method = RequestMethod.POST)
public ModelAndView registering(HttpServletRequest request,
       @RequestParam("email") String email,
       @RequestParam("username") String nickName,
       @RequestParam("password") String password,
       HttpServletResponse response) {
    logger.info("正在注册   registering START");
    ModelAndView mav = new ModelAndView();
    mav.setViewName("homePage/registerPage");

    email = email==null?"":email.trim();
    nickName = nickName==null?"":nickName.trim();
    password = password==null?"":password.trim();

    UserRegisterServiceRequestDTO requestDTO = new UserRegisterServiceRequestDTO();
    requestDTO.setEmail(email);
    requestDTO.setNickName(nickName);
    requestDTO.setPassword(password);

    if(requestDTO != null){
       userManagerService.addUser(requestDTO);
       mav.setViewName("redirect:/home/homePage/logining.do");
    }else{
       mav.addObject("errorTips", "您输入数据有误!");
       request.getSession().setAttribute("information", null);
    }

    logger.info("正在注册   registering End");
    return mav;
}

}

wendal

8楼•572天前

spring会认nutz的注解????

@Inject
private UserManagerServiceImpl  userManagerService;

这个绝对不会生效, 通过下面的方式取

Mvcs.ctx().getDefaultIoc(UserManagerServiceImpl.class)

子寒磊(ds25)

9楼•572天前

@wendal 直接用Mvcs.ctx().getDefaultIoc(UserManagerServiceImpl.class)将
@Inject
private UserManagerServiceImpl userManagerService; 替代吗？

wendal

10楼•572天前

恩，用的时候从nutz ioc取

ps，为啥不用spring 的ioc呢

子寒磊(ds25)

11楼•572天前

@wendal

现在又出现一个问题:当我在类中直接使用
Mvcs.ctx().getDefaultIoc(UserManagerServiceImpl.class) 时，会出现
Multiple markers at this line
- Syntax error on token "ctx", Identifier expected after this
token
- Syntax error on token ".", { expected

请问这是什么原因？

wendal

12楼•572天前

@ds25 版本旧，改成 Mvcs.ctx.getDefaultIoc

子寒磊(ds25)

13楼•572天前

@wendal

改成 Mvcs.ctx.getDefaultIoc(UserManagerServiceImpl.class);
会出现
Syntax error on token "getDefaultIoc", Identifier expected after this token

这也是版本问题吗

wendal

14楼•572天前

@ds25 啥版本？