File JSP上载文件失败
我将构建一个简单的jspfile来使用Servlet处理上传文件。在执行时，它显示以下消息File JSP上载文件失败,file,jsp,http,upload,File,Jsp,Http,Upload,我将构建一个简单的jspfile来使用Servlet处理上传文件。在执行时，它显示以下消息 demo Fail: org.apache.catalina.connector.RequestFacade cannot be cast to org.apache.tomcat.util.http.fileupload.RequestContext 您能告诉我如何将HTTP请求转换为RequestContext吗 下面是我的jsp首页代码 <%@ page language="ja
demo Fail: org.apache.catalina.connector.RequestFacade cannot
be cast to org.apache.tomcat.util.http.fileupload.RequestContext
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title Test Upload</title>
</head>
<body>
<form action="uploadFile" method="post" enctype="multipart/form-data">
<input type="file" name="file" />
<input type="submit" />
</form>
</body>
</html>
插入标题测试上载
import java.io.*;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import java.sql.*;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import javax.servlet.*;
import javax.servlet.http.*;
import org.apache.tomcat.util.http.fileupload.FileItem;
import org.apache.tomcat.util.http.fileupload.FileItemFactory;
import org.apache.tomcat.util.http.fileupload.FileUploadException;
import org.apache.tomcat.util.http.fileupload.RequestContext;
import org.apache.tomcat.util.http.fileupload.disk.DiskFileItemFactory;
import org.apache.tomcat.util.http.fileupload.servlet.ServletFileUpload;
/**
* Servlet implementation class getLogin
*/
public class uploadFile extends HttpServlet {
private static final long serialVersionUID = 17864986468494864L;
// location to store file uploaded
private static final String UPLOAD_DIRECTORY = "upload";
// upload settings
public uploadFile() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//doPost(request, response);
//throw new ServletException("GET method used with " + getClass( ).getName( )+": POST method required.");
request.getRequestDispatcher("/WEB-INF/upload.jsp").forward(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("demo");
if (!ServletFileUpload.isMultipartContent(request)) {
// if not, we stop here
PrintWriter writer = response.getWriter();
writer.println("Error: Form must has enctype=multipart/form-data.");
writer.flush();
return;
}
// configures upload settings
DiskFileItemFactory factory = new DiskFileItemFactory();
// sets temporary location to store files
factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
ServletFileUpload upload = new ServletFileUpload(factory);
// constructs the directory path to store upload file
// this path is relative to application's directory
String uploadPath = getServletContext().getRealPath("")+ File.separator + UPLOAD_DIRECTORY;
// creates the directory if it does not exist
File uploadDir = new File(uploadPath);
if (!uploadDir.exists()) {
uploadDir.mkdir();
}
try {
// parses the request's content to extract file data
System.out.println(uploadPath);
List<FileItem> formItems = upload.parseRequest((RequestContext)request);
if (formItems != null && formItems.size() > 0) {
// iterates over form's fields
for (FileItem item : formItems) {
// processes only fields that are not form fields
if (!item.isFormField()) {
String fileName = new File(item.getName()).getName();
String filePath = uploadPath + File.separator + fileName;
File storeFile = new File(filePath);
// C:\tomcat\apache-tomcat-7.0.40\webapps\data\
// saves the file on disk
item.write(storeFile);
request.setAttribute("message","Upload has been done successfully!");
System.out.println("demo Success");
}
}
}
} catch (Exception ex) {
request.setAttribute("message","There was an error: " + ex.getMessage());
System.out.println("demo Fail: " + ex.getMessage() );
}
}
}
import java.io.*；
导入java.net.URL；
导入java.net.URLConnection；
导入java.net.urlcoder；
导入java.sql.*；
导入java.util.Enumeration；
导入java.util.Iterator；
导入java.util.List；
导入javax.servlet.*；
导入javax.servlet.http.*；
导入org.apache.tomcat.util.http.fileupload.FileItem；
导入org.apache.tomcat.util.http.fileupload.FileItemFactory；
导入org.apache.tomcat.util.http.fileupload.FileUploadException；
导入org.apache.tomcat.util.http.fileupload.RequestContext；
导入org.apache.tomcat.util.http.fileupload.disk.DiskFileItemFactory；
导入org.apache.tomcat.util.http.fileupload.servlet.ServletFileUpload；
/**
*Servlet实现类getLogin
*/
公共类上载文件扩展HttpServlet{
私有静态最终长serialVersionUID=17864986468494864L；
//存储上载文件的位置
私有静态最终字符串上载\u DIRECTORY=“UPLOAD”；
//上载设置
公共上传文件（）{
超级（）；
//TODO自动生成的构造函数存根
}
/**
*@参见HttpServlet#doGet（HttpServletRequest请求，HttpServletResponse响应）
*/
受保护的void doGet（HttpServletRequest请求，HttpServletResponse响应）抛出ServletException，IOException{
//TODO自动生成的方法存根
//doPost（请求、响应）；
//抛出新的ServletException（“GET方法与“+getClass（）.getName（）+”：POST方法一起使用。”）；
request.getRequestDispatcher（“/WEB-INF/upload.jsp”）.forward（请求，响应）；
}
/**
*@请参阅HttpServlet#doPost（HttpServletRequest请求，HttpServletResponse响应）
*/
受保护的void doPost（HttpServletRequest请求、HttpServletResponse响应）引发ServletException、IOException{
System.out.println（“演示”）；
如果（！ServletFileUpload.isMultipartContent（请求））{
//如果不是，我们就到此为止
PrintWriter=response.getWriter（）；
println（“错误：表单必须有enctype=multipart/formdata.”）；
writer.flush（）；
返回；
}
//配置上载设置
DiskFileItemFactory=新的DiskFileItemFactory（）；
//设置存储文件的临时位置
setRepository（新文件（System.getProperty（“java.io.tmpdir”））；
ServletFileUpload upload=新的ServletFileUpload（工厂）；
//构造用于存储上载文件的目录路径
//此路径相对于应用程序的目录
字符串uploadPath=getServletContext（）.getRealPath（“”+File.separator+UPLOAD\u目录；
//如果目录不存在，则创建该目录
文件上传目录=新文件（上传路径）；
如果（！uploadDir.exists（））{
uploadDir.mkdir（）；
}
试一试{
//解析请求的内容以提取文件数据
System.out.println（上传路径）；
List formItems=upload.parseRequest（（RequestContext）请求）；
if（formItems！=null&&formItems.size（）>0）{
//迭代窗体的字段
用于（文件项：表单项）{
//仅处理非表单字段的字段
如果（！item.isFormField（））{
字符串文件名=新文件（item.getName（））.getName（）；
字符串filePath=uploadPath+File.separator+fileName；
文件存储文件=新文件（文件路径）；
//C:\tomcat\apache-tomcat-7.0.40\webapps\data\
//将文件保存在磁盘上
item.write（存储文件）；
setAttribute（“消息”，“上传成功！”）；
System.out.println（“演示成功”）；
}
}
}
}捕获（例外情况除外）{
setAttribute（“消息”，“出现错误：”+ex.getMessage（））；
System.out.println（“演示失败：+ex.getMessage（））；
}
}
}
@WebServlet("/yourPattern")
@MultipartConfig
public class UploadFile extends HttpServlet { //...
Part filePart = request.getPart("file"); // Retrieves <input type="file" name="file">
InputStream filecontent = filePart.getInputStream();
partfilepart=request.getPart（“文件”）；//检索
InputStream filecontent=filePart.getInputStream（）；
List<FileItem> formItems = upload.parseRequest((RequestContext)request);
if (formItems != null && formItems.size() > 0) {
// iterates over form's fields
for (FileItem item : formItems) {
if (!item.isFormField()) { //...
List formItems=upload.parseRequest（（RequestContext）请求）；
if（formItems！=null&&formItems.size（）>0）{
//迭代窗体的字段
用于（文件项：表单项）{
如果（！item.isFormField（））{/。。。
有关更多信息，请参阅另一篇文章。当您从enctype=multipart/Form data的表单中获取参数而不使用标准时，在Tomcat 7和Servlet 3.0上尝试此错误
@WebServlet("/yourPattern")
@MultipartConfig
public class UploadFile extends HttpServlet { //...
Part filePart = request.getPart("file"); // Retrieves <input type="file" name="file">
InputStream filecontent = filePart.getInputStream();
partfilepart=request.getPart（“文件”）；//检索
InputStream filecontent=filePart.getInputStream（）；
List<FileItem> formItems = upload.parseRequest((RequestContext)request);
if (formItems != null && formItems.size() > 0) {
// iterates over form's fields
for (FileItem item : formItems) {
if (!item.isFormField()) { //...
List formItems=upload.parseRequest（（RequestContext）请求）；
if（formItems！=null&&formItems.size（）>0）{
//迭代窗体的字段
用于（文件项：表单项）{
如果（！item.isFormField（））{/。。。
有关更多信息，请参阅其他帖子。这是由于导入不正确造成的。请下载此文件并将其放入WEB-INF/lib文件夹中。如果其他人仍在寻找此文件（如我），请按以下所列正确导入
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;