无法将字段设置为com.sun.proxy。$ Proxy
对于文件上传，我试图在我的Spring Controller中注入并使用Validator，如下所示：
@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validation者：
@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"); } } }
这是我要validation的File对象：
public class File { private String name; private MultipartFile file; public File() { } public File(MultipartFile file) { this.file = file; } public String getName() { return name; } public void setName(String name) { this.name = name; } public MultipartFile getFile() { return file; } public void setFile(MultipartFile file) { this.file = file; } }
这是我尝试启动应用程序时出现的错误：
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$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:569) ~[spring-beans-4.2.6.RELEASE.jar:4.2.6.RELEASE] ... 19 common frames omitted 2016-06-09 15:12:39.909 WARN 4896 --- [ main] osboot.SpringApplication : Error handling failed (Error creating bean with name 'delegatingApplicationListener' defined in class path resource [org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.class]: BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration': Initialization of bean failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'org.springframework.context.annotation.ConfigurationClassPostProcessor.importRegistry' is defined)
我不知道发生了什么。 有人可以帮忙吗？
无法将’FileValidator’字段’FileController.validator’设置为’com.sun.proxy。$ Proxy101′
FileValidator是一个类，而不是一个接口。
com.sun.proxy.$Proxy101是一个接口代理，而不是类代理。
有两种主要方法可以解决这个问题。 通过接口注入validation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，将有其他方法来实现这两个解决方案。
在类FileController中自动FileValidator(class)的接口。 这样做不需要您指定@Qualifier，如下所述：
@Autowired IFileValidator filevalidator;