Java 无法将字段设置为com.sun.proxy.$proxy
对于文件上载,我尝试在我的Spring控制器中插入并使用验证程序,如下所示:Java 无法将字段设置为com.sun.proxy.$proxy,java,spring,spring-mvc,spring-boot,spring-aop,Java,Spring,Spring Mvc,Spring Boot,Spring Aop,对于文件上载,我尝试在我的Spring控制器中插入并使用验证程序,如下所示: @RestController @RequestMapping("/api") public class FileController{ @Autowired private MessageSource messageSource; @Autowired FileValidator validator; @InitBinder("file") public void
@RestController
@RequestMapping("/api")
public class FileController{
@Autowired
private MessageSource messageSource;
@Autowired
FileValidator validator;
@InitBinder("file")
public void initBinderFile(WebDataBinder binder) {
binder.setValidator(validator);
}
@RequestMapping(value = "/fileUpload2", method = RequestMethod.POST, produces = {"text/plain"})
@PreAuthorize("hasAuthority('ADMINISTRATOR')")
public String singleFileUpload2(@Valid @ModelAttribute("file") File file, BindingResult result) throws IOException {
if (result.hasErrors()) {
String errorString = "";
for (ObjectError error : result.getAllErrors()) {
errorString = errorString.concat(messageSource.getMessage(error.getCode(), new String[]{}, Locale.ENGLISH)+"\n");
}
return errorString;
} else {
MultipartFile multipartFile = file.getFile();
String fileName = multipartFile.getOriginalFilename();
System.out.println("Fetching file: "+fileName);
return messageSource.getMessage("upload.file.success", new String[]{}, Locale.ENGLISH);
}
}
}
这是我的验证器:
@Component
public class FileValidator implements Validator {
@Override
public boolean supports(Class<?> clazz) {
return File.class.isAssignableFrom(clazz);
}
@Override
public void validate(Object obj, Errors errors) {
File file = (File) obj;
if (file.getFile().getSize() == 0) {
errors.rejectValue("file", "missing.file");
} else try {
if (file.getFile().getBytes().length > 2097152l) {
errors.rejectValue("file", "upload.file.error.size");
}
if(!file.getFile().getContentType().equalsIgnoreCase("text/html")){
errors.rejectValue("file", "incorrect.file.type");
}
} catch (IOException ex) {
errors.rejectValue("file", "upload.file.error");
}
}
}
以下是我尝试启动应用程序时遇到的错误:
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'fileController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.enterprise.springapp.web.validators.FileValidator com.eurodyn.springapp.web.FileController.validator; nested exception is java.lang.IllegalArgumentException: Can not set com.enterprise.springapp.web.validators.FileValidator field com.enterprise.springapp.web.FileController.validator to com.sun.proxy.$Proxy101
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839) ~[spring-context-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538) ~[spring-context-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118) ~[spring-boot-1.3.5.RELEASE.jar:1.3.5.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:766) [spring-boot-1.3.5.RELEASE.jar:1.3.5.RELEASE]
at org.springframework.boot.SpringApplication.createAndRefreshContext(SpringApplication.java:361) [spring-boot-1.3.5.RELEASE.jar:1.3.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:307) [spring-boot-1.3.5.RELEASE.jar:1.3.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1191) [spring-boot-1.3.5.RELEASE.jar:1.3.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1180) [spring-boot-1.3.5.RELEASE.jar:1.3.5.RELEASE]
at com.enterprise.springapp.SpringApp.main(SpringApp.java:30) [classes/:na]
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.enterprise.springapp.web.validators.FileValidator com.enterprise.springapp.web.FileController.validator; nested exception is java.lang.IllegalArgumentException: Can not set com.enterprise.springapp.web.validators.FileValidator field com.enterprise.springapp.web.FileController.validator to com.sun.proxy.$Proxy101
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:573) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
... 17 common frames omitted
Caused by: java.lang.IllegalArgumentException: Can not set com.enterprise.springapp.web.validators.FileValidator field com.enterprise.springapp.web.FileController.validator to com.sun.proxy.$Proxy101
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167) ~[na:1.8.0_45]
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171) ~[na:1.8.0_45]
at sun.reflect.UnsafeObjectFieldAccessorImpl.set(UnsafeObjectFieldAccessorImpl.java:81) ~[na:1.8.0_45]
at java.lang.reflect.Field.set(Field.java:764) ~[na:1.8.0_45]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:569) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE]
... 19 common frames omitted
2016-06-09 15:12:39.909 WARN 4896 --- [ main] o.s.boot.SpringApplication : Error handling failed (Error creating bean with name 'delegatingApplicationListener' defined in class path resource [org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.class]: BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration': Initialization of bean failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'org.springframework.context.annotation.ConfigurationClassPostProcessor.importRegistry' is defined)
我不知道发生了什么事。有人能帮忙吗
无法将“FileValidator”字段“FileController.validator”设置为“com.sun.proxy.$Proxy101”
FileValidator
是一个类,而不是一个接口
com.sun.proxy.$Proxy101
是接口代理,而不是类代理
解决这个问题有两种主要方法。通过接口注入验证器,例如:
@Autowired @Qualifier("fileValidator")
private Validator fileValidator;
或启用类代理,例如:
@SpringBootApplication
@EnableAspectJAutoProxy(proxyTargetClass = true)
public class Application {
这些只是示例,还有其他方法可以实现这两种解决方案。在类
FileController
中自动连接FileValidator(class)
的接口。
这样做不需要您指定@Qualifier,如下所述:
@Autowired
IFileValidator filevalidator;
非常感谢你的帮助!我应用了第二个解决方案,它成功了。问题不在于
FileValidator
,而在于FileController
@zeroplagl。问题在于它们之间的交互方式——这不仅仅是其中一个。不。Spring尝试为FileController
创建代理,然后无法设置验证程序。错误消息不能更明确。@zeroflagL$Proxy101
引用了FileValidator
bean的代理,该代理不能分配给FileValidator
类型的字段,因为它实现了Validator
,而不是扩展FileValidator
。切勿在字段上使用@Autowired
。2.有一个web安全配置,因此在控制器方法上放置@PreAuthorize(“hasAuthority('ADMINISTRATOR')”)
没有多大意义。这两点的结合是问题的原因。@zeroflagL这些都是相当宽泛的陈述。这两件事你都反对占有一席之地。@OrangeDog Spring开发人员自己不鼓励在字段上使用@Autowired
。但是如果你有地方放它,那么你当然可以自由使用它。
@Autowired
IFileValidator filevalidator;