Jav*_*avi 28 java forms spring file-upload spring-mvc
MaxUploadSizeExceededException当我上传大小超过允许的最大值的文件时,会出现异常.我想在出现此异常时显示错误消息(如验证错误消息).如何在Spring 3中处理此异常以执行此类操作？
谢谢.
小智 33
我终于想出了一个使用HandlerExceptionResolver工作的解决方案.
将多部分解析器添加到Spring配置:
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- the maximum size of an uploaded file in bytes -->
<!-- <property name="maxUploadSize" value="10000000"/> -->
<property name="maxUploadSize" value="1000"/>
</bean>
Model - UploadedFile.java:
package com.mypkg.models;
import org.springframework.web.multipart.commons.CommonsMultipartFile;
public class UploadedFile
{
private String title;
private CommonsMultipartFile fileData;
public String getTitle()
{
return title;
}
public void setTitle(String title)
{
this.title = title;
}
public CommonsMultipartFile getFileData()
{
return fileData;
}
public void setFileData(CommonsMultipartFile fileData)
{
this.fileData = fileData;
}
}
查看 - /upload.jsp:
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<title>Test File Upload</title>
</head>
<body>
<h1>Select a file to upload</h1>
<c:if test="${not empty errors}">
<h2 style="color:red;">${errors}.</h2>
</c:if>
<form:form modelAttribute="uploadedFile" method="post" enctype="multipart/form-data" name="uploadedFileform" id="uploadedFileform">
<table width="600" border="0" align="left" cellpadding="0" cellspacing="0" id="pdf_upload_form">
<tr>
<td width="180"><label class="title">Title:</label></td>
<td width="420"><form:input id="title" path="title" cssClass="areaInput" size="30" maxlength="128"/></td>
</tr>
<tr>
<td width="180"><label class="title">File:</label></td>
<td width="420"><form:input id="fileData" path="fileData" type="file" /></td>
</tr>
<tr>
<td width="180"></td>
<td width="420"><input type="submit" value="Upload File" /></td>
</tr>
</table>
</form:form>
</body>
</html>
Controller - FileUploadController.java:package com.mypkg.controllers;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.multipart.MaxUploadSizeExceededException;
import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.ModelAndView;
import com.mypkg.models.UploadedFile;
@Controller
public class FileUploadController implements HandlerExceptionResolver
{
@RequestMapping(value = "/upload", method = RequestMethod.GET)
public String getUploadForm(Model model)
{
model.addAttribute("uploadedFile", new UploadedFile());
return "/upload";
}
@RequestMapping(value = "/upload", method = RequestMethod.POST)
public String create(UploadedFile uploadedFile, BindingResult result)
{
// Do something with the file
System.out.println("######### File Uploaded with Title: " + uploadedFile.getTitle());
System.out.println("######### Creating local file: /var/test-file-upload/" + uploadedFile.getFileData().getOriginalFilename());
try
{
InputStream in = uploadedFile.getFileData().getInputStream();
FileOutputStream f = new FileOutputStream(
"/var/test-file-upload/" + uploadedFile.getFileData().getOriginalFilename());
int ch = 0;
while ((ch = in.read()) != -1)
{
f.write(ch);
}
f.flush();
f.close();
}
catch (IOException e)
{
e.printStackTrace();
}
return "redirect:/";
}
/*** Trap Exceptions during the upload and show errors back in view form ***/
public ModelAndView resolveException(HttpServletRequest request,
HttpServletResponse response, Object handler, Exception exception)
{
Map<String, Object> model = new HashMap<String, Object>();
if (exception instanceof MaxUploadSizeExceededException)
{
model.put("errors", exception.getMessage());
} else
{
model.put("errors", "Unexpected error: " + exception.getMessage());
}
model.put("uploadedFile", new UploadedFile());
return new ModelAndView("/upload", model);
}
}
========================================================================
谢谢你解决这个史蒂夫.我试图解决几个小时的问题.
关键是让控制器实现HandlerExceptionResolver并添加resolveException方法.
--Bob
这是一个古老的问题，因此我将其添加到正在努力使之与Spring Boot 2兼容的未来人们（包括未来我）中。
首先，您需要配置spring应用程序（在属性文件中）：
spring.servlet.multipart.max-file-size=10MB
spring.servlet.multipart.max-request-size=10MB
如果您使用的是嵌入式Tomcat（并且很可能是标准配置），那么配置Tomcat使其不取消大型请求也很重要。
server.tomcat.max-swallow-size=-1
或至少将其设置为相对较大的尺寸
server.tomcat.max-swallow-size=100MB
如果您不为Tomcat设置maxSwallowSize，则可能会浪费大量时间来调试为什么会处理错误，但浏览器却没有响应-这是因为没有此配置，Tomcat将会取消请求，即使您在日志中看到该应用程序正在处理错误，浏览器已经收到Tomcat的取消请求，并且不再侦听响应。
为了处理MaxUploadSizeExceededException，可以添加带有ExceptionHandler的ControllerAdvice。
这是Kotlin中的一个简单示例，该示例简单地将Flash属性设置为错误并重定向到某些页面：
@ControllerAdvice
class FileSizeExceptionAdvice {
@ExceptionHandler(MaxUploadSizeExceededException::class)
fun handleFileSizeException(
e: MaxUploadSizeExceededException,
redirectAttributes: RedirectAttributes
): String {
redirectAttributes.addFlashAttribute("error", "File is too big")
return "redirect:/"
}
}
注意：如果要直接在控制器类中使用ExceptionHandler处理MaxUploadSizeExceededException，则应配置以下属性：
spring.servlet.multipart.resolve-lazily=true
否则，将在请求映射到控制器之前触发该异常。
使用控制器建议
@ControllerAdvice
public class GlobalExceptionHandler {
@ExceptionHandler(MaxUploadSizeExceededException.class)
public ModelAndView handleMaxUploadException(MaxUploadSizeExceededException e, HttpServletRequest request, HttpServletResponse response){
ModelAndView mav = new ModelAndView();
boolean isJson = request.getRequestURL().toString().contains(".json");
if (isJson) {
mav.setView(new MappingJacksonJsonView());
mav.addObject("result", "nok");
}
else mav.setViewName("uploadError");
return mav;
}
}
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