更新:我已经观察到传递空值的原因是enctype="multipart/form-data"
,但是需要该部分才能将文件传递给控制器。以下问题仍然存在。
我一直在尝试设置一个允许用户上传文档的Spring MVC页面。我环顾四周,似乎对如何实现这一点有了一个大概(使用“commons-fileupload”和“commons-io”),所以以下是我的视图,控制器和模型。
查看:
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form" %>
<%@ page session="false" %>
<html>
<head>
<title>Upload Document</title>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">
</script>
<script type="text/javascript" src="resources/rulesextractor.js"></script>
<link rel="stylesheet" type="text/css" href="./resources/css/rulesextractor.css" />
</head>
<body>
<c:import url = "./header.jsp">
<c:param name = "title" value = "Upload Document"/>
<c:param name = "region" value = "${region}"/>
</c:import>
<br>
Please choose a Document to upload
<br>
<form:form method="POST" modelAttribute="uploadForm" commandName="uploadForm" name="uploadForm" id="uploadForm" enctype="multipart/form-data">
<form:input path="fileData" name="fileData" type="file"/>
<br>
<input type="submit" name="submit" value="Submit" id="subbtn"/>
<input type="button" value="Main Menu" onclick="back();"/>
</form:form>
</body>
</html>
控制器:
@Controller
public class UploadController extends BaseController {
private static final Logger logger = LoggerFactory.getLogger(FlowController.class);
//@Autowired
//private UserPreferences userPreferences;
@Autowired
GenericSearchBO genericSearchBO;
@RequestMapping(value = "upload", method = RequestMethod.GET)
public String getUploadPage(Model m){
logger.info("UploadController: Getting Upload page");
updateRegionOnModel(m);
m.addAttribute(new UploadForm());
return "/pages/upload";
}
@RequestMapping(method = RequestMethod.POST)
public String create(@Valid UploadForm UploadForm, BindingResult result){
if (result.hasErrors())
{
for(ObjectError error : result.getAllErrors())
{
System.err.println("Error: " + error.getCode() + " - " + error.getDefaultMessage());
}
return "/pages/upload";
}
// Some type of file processing...
System.err.println("-------------------------------------------");
//.getOriginalFilename()
System.err.println("Test upload: " + UploadForm.getFileData());
System.err.println("-------------------------------------------");
return "redirect:/pages/upload";
}
}
型号:
public class UploadForm {
private CommonsMultipartFile fileData;
public CommonsMultipartFile getFileData() {
System.out.println("REACHED GET METHOD");
return fileData;
}
public void setFileData(CommonsMultipartFile fileData) {
System.out.println("REACHED SET METHOD");
this.fileData = fileData;
}
}
我是Spring的新手,一般都是MVC,但我正慢慢掌握它。这里的问题是我实际上正在进入Controller的public String create(@Valid UploadForm UploadForm, BindingResult result)
方法,但是UploadForm作为一个空值被传递,我不能,在我的生活中,弄清楚它并且它变得非常令人沮丧。任何帮助或提示将不胜感激。谢谢!
答案 0 :(得分:1)
在servlet.xml中,您必须添加:
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- one of the properties available; the maximum file size in bytes -->
<property name="maxUploadSize" value="100000"/>
</bean>
答案 1 :(得分:0)
这是使用multipart / form-data
实现的<form:form id="" action="xxx.do" method="post"
modelAttribute="uploadFile" enctype="multipart/form-data">
<form:input path="data" id="data" type="file" />
</form:form>
模型类
public class uploadFile{
private CommonsMultipartFile data;
//getter and setter
}
在控制器中
@RequestMapping(value = "/upload", method = RequestMethod.POST)
public ModelAndView fileUpload(uploadFile fileuploaded,
BindingResult result,
HttpSession session){
...
}
阅读文件
BufferedReader br = new BufferedReader(
new InputStreamReader(fileuploaded.getFileData().getInputStream()));
答案 2 :(得分:0)
index.jsp
<a href="uploadform">Upload Image</a>
Emp.java
package com.javatpoint;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.commons.CommonsMultipartFile;
import org.springframework.web.servlet.ModelAndView;
@Controller
public class HelloController {
private static final String UPLOAD_DIRECTORY ="/images";
@RequestMapping("uploadform")
public ModelAndView uploadForm(){
return new ModelAndView("uploadform");
}
@RequestMapping(value="savefile",method=RequestMethod.POST)
public ModelAndView saveimage( @RequestParam CommonsMultipartFile file,
HttpSession session) throws Exception{
ServletContext context = session.getServletContext();
String path = context.getRealPath(UPLOAD_DIRECTORY);
String filename = file.getOriginalFilename();
System.out.println(path+" "+filename);
byte[] bytes = file.getBytes();
BufferedOutputStream stream =new BufferedOutputStream(new FileOutputStream(
new File(path + File.separator + filename)));
stream.write(bytes);
stream.flush();
stream.close();
return new ModelAndView("uploadform","filesuccess","File successfully saved!");
}
}
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>spring</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>spring</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
spring-servlet.xml
Here, you need to create a bean for CommonsMultipartResolver.
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="com.javatpoint"></context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>
</beans>
uploadform.jsp
Here form must be method="post" and enctype="multipart/form-data".
<%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<!DOCTYPE html>
<html>
<head>
<title>Image File Upload</title>
</head>
<body>
<h1>File Upload Example - JavaTpoint</h1>
<h3 style="color:red">${filesuccess}</h3>
<form:form method="post" action="savefile" enctype="multipart/form-data">
<p><label for="image">Choose Image</label></p>
<p><input name="file" id="fileToUpload" type="file" /></p>
<p><input type="submit" value="Upload"></p>
</form:form>
</body>
</html>