spring 奇怪的异常：“名称不能为空或为空！”
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Strange exception: "Name must not be null or empty!"
提问by Sam
I'm experiencing a strange error in a Spring project, which is the following:
我在 Spring 项目中遇到一个奇怪的错误，如下所示：
SEVERE: Servlet.service() for servlet [calzoneServlet] in context with path [/calzone] threw exception [Request processing failed; nested exception is org.springframework.dao.InvalidDataAccessApiUsageException: Name must not be null or empty!; nested exception is java.lang.IllegalArgumentException: Name must not be null or empty!] with root cause java.lang.IllegalArgumentException: Name must not be null or empty!
严重：servlet [calzoneServlet] 的 Servlet.service() 在路径为 [/calzone] 的上下文中引发异常 [请求处理失败；嵌套异常是 org.springframework.dao.InvalidDataAccessApiUsageException: Name must not be null or empty!; 嵌套异常是 java.lang.IllegalArgumentException: Name must not be null or empty!] 根本原因 java.lang.IllegalArgumentException: Name must not be null or empty!
In this project, all models are mapped to the database using hibernate and jpa. The front-end uses Twitter Bootstrap (with spring form validation, etc)
在这个项目中，所有模型都使用 hibernate 和 jpa 映射到数据库。前端使用 Twitter Bootstrap（带有 spring 表单验证等）
The error occurs at different parts of the program, one of which is a controller to activate a user account (code below). To me this looks like some sort of validation error, but it isn't an error I have ever defined. Since I can't pinpoint the exact location of the error, I'll only provide the controller below. It is noteworthy that any debug messages (whether it be through the logger or just a plain old sysout) in the activateUsermethod do not get displayed.
该错误发生在程序的不同部分，其中之一是激活用户帐户的控制器（下面的代码）。对我来说，这看起来像是某种验证错误，但这不是我定义过的错误。由于我无法确定错误的确切位置，因此我将仅提供下面的控制器。值得注意的是，该方法中的任何调试消息（无论是通过记录器还是只是一个普通的旧系统输出）activateUser都不会显示。
All dependencies (pom.xml) can be found here: http://pastebin.com/fs7SG0W2Web.xml here: http://pastebin.com/vAJh29AwThe entire stacktrace can be found here: http://codepad.org/p0Yt5hi2(on codepad, because it has horizontal scrolling)
所有依赖项 (pom.xml) 都可以在这里找到：http: //pastebin.com/fs7SG0W2 Web.xml 在这里：http: //pastebin.com/vAJh29Aw 整个堆栈跟踪可以在这里找到：http: //codepad.org /p0Yt5hi2（在键盘上，因为它具有水平滚动功能）
Does anyone have any idea why this error could be happening, or have any clue as to how I can find out why it's happening?
有没有人知道为什么会发生这个错误，或者有什么线索可以知道我如何找出它发生的原因？
@Controller
public class ActivateAccountController {
final Logger logger = LoggerFactory.getLogger(getClass());
@RequestMapping(value = "/activate/{keyString}", method = RequestMethod.GET)
public String activateUser(@PathVariable String keyString) {
ConfigurableApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
KeyService keyService = (KeyService) context.getBean("keyService");
UserService userService = (UserService) context.getBean("userService");
User user;
try {
logger.error("DID I GET HERE?");
user = keyService.findUserByKey(keyString);
} catch (KeyNotFoundException ex) {
return "ActivatedNotAccount";
} finally {
// Close the application context in every case
context.close();
}
// Activate the in-memory user
userService.activateUser(user);
// Delete the key from the database
keyService.deleteKey(keyString);
// Finally, update the user in the database
userService.updateUser(user);
logger.info("Acticated user with ID \"{}\", First name: \"{}\", Last name: \"{}\" and username: \"{}\"",
user.getId(), user.getPerson().getFirstName(), user.getPerson().getLastName(), user.getUsername());
return "ActivatedAccount";
}
}
回答by Emerson Farrugia
Your KeyServiceis calling some Spring Data JPA repository with a method findKeyByKeyString()method. That method is causing Spring Data JPA to explode because some query parameter is missing.
您KeyService正在使用方法findKeyByKeyString()方法调用一些 Spring Data JPA 存储库。该方法导致 Spring Data JPA 爆炸，因为缺少某些查询参数。
Put a conditional breakpoint on org.springframework.data.jpa.repository.query.StringQuery.getBindingFor(StringQuery.java:104)that matches if !StringUtils.hasText(name)to see what's going on, or review the findKeyByKeyString()method.
org.springframework.data.jpa.repository.query.StringQuery.getBindingFor(StringQuery.java:104)如果!StringUtils.hasText(name)要查看发生了什么或查看findKeyByKeyString()方法，请在匹配项上放置条件断点。
回答by uthomas
EDIT: As @Gilbertoca pointed out I indeed had to use @Param. Source of my confusion was that I used @QueryParam annotation by accident.
编辑：正如@Gilbertoca 指出的那样，我确实必须使用@Param。我困惑的根源是我不小心使用了 @QueryParam 注释。
So if you use @Param it'll work.
所以如果你使用@Param 它会起作用。
Original response:
原回复：
I got exactly the same and took some time while I figured out what was the problem: I used JpaRepository interface with a method annotated like
我完全一样，花了一些时间才弄清楚问题出在哪里：我使用了 JpaRepository 接口和一个注释如下的方法
@Query(value = "SELECT * FROM table WHERE property=:something", nativeQuery = true).
As it turned out in this context named parameters are not supported. It started to work for me after I changed to:
事实证明，在此上下文中不支持命名参数。在我改为：
@Query(value = "SELECT * FROM table WHERE property=(?1)", nativeQuery = true).
(brackets are important, otherwise it didn't work).
（括号很重要，否则它不起作用）。
回答by Arun Gopalpuri
I had the same exception and I was missing @Param("appname") in method args:
我有同样的例外，我在方法 args 中缺少 @Param("appname") ：
@Query("SELECT p.preferenceId.userId FROM Preference p WHERE p.preferenceId.appName = :appname") List getAppUsers(@Param("appname")String appname);
@Query("SELECT p.preferenceId.userId FROM Preference p WHERE p.preferenceId.appName = :appname") List getAppUsers( @Param("appname")String appname);
