java.lang.NoSuchMethodException: [org.springframework.web.multipart.MultipartFile;.<init>()

java.lang.NoSuchMethodException: [org.springframework.web.multipart.MultipartFile;.<init>()at java.lang.Class.getConstructor0(Class.java:2721)at java.lang.Class.getDeclaredConstructor(Class.java:2002)at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:104)at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.createAttribute(ModelAttributeMethodProcessor.java:132)at org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor.createAttribute(ServletModelAttributeMethodProcessor.java:81)at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:103)at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:75)at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:156)at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:117)at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:563)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:399)at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:317)at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:204)at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:182)at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:311)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)at java.lang.Thread.run(Thread.java:722)2012-11-07 17:09:48,932 ["http-bio-80"-exec-3] ERROR [500.jsp] - Could not instantiate bean class [[Lorg.springframework.web.multipart.MultipartFile;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lorg.springframework.web.multipart.MultipartFile;.<init>()org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lorg.springframework.web.multipart.MultipartFile;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lorg.springframework.web.multipart.MultipartFile;.<init>()at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:107)at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.createAttribute(ModelAttributeMethodProcessor.java:132)at org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor.createAttribute(ServletModelAttributeMethodProcessor.java:81)at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:103)at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:75)at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:156)at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:117)at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:563)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:399)at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:317)at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:204)at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:182)at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:311)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)at java.lang.Thread.run(Thread.java:722)Caused by: java.lang.NoSuchMethodException: [Lorg.springframework.web.multipart.MultipartFile;.<init>()at java.lang.Class.getConstructor0(Class.java:2721)at java.lang.Class.getDeclaredConstructor(Class.java:2002)at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:104)... 61 more

出现这个错误的原因是 在方法里面 MultipartFile[] files没有加入@RequestParam，改成如下:
public String save(@RequestParam(value="files", required=true) MultipartFile[] files){
}