网上 fuzhe(令狐虫) 给了一个下载文件的servlet 程序，但在我这有点问题？？？？

Question

这样修改试一试：
 <servlet-mapping>
    <servlet-name>download</servlet-name>
    <url-pattern>/download/*</url-pattern><!--here edited-->
  </servlet-mapping>

Answer 1

不可以把Download的源代码给帖出来吗？

Answer 2

部署没有问题:
源代码:(提示这是 fuzhe(令狐虫) 在这转帖,和我修改一两个地方)import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;public class Download extends HttpServlet {        private static final String CONTENT_TYPE = "text/html; charset=GBK";          //Initialize global variables
          public void init() throws ServletException {
          }
          //Process the HTTP Get request
          public void doGet(HttpServletRequest request, HttpServletResponse response)
              throws ServletException, IOException {
                //HttpServletRequestWrapper httpReqWrapper = (HttpServletRequestWrapper) request;
                //HttpServletRequest httpRequest =(HttpServletRequest)httpReqWrapper.getRequest();
                try {
                      downloadArtifact(request, response);
            }catch (Exception e) {
              e.printStackTrace();
              RequestDispatcher dispatcher = this.getServletContext().
              getRequestDispatcher("/Error.jsp");
              dispatcher.forward(request, response);//              httpServletRequest.setAttribute("message", "修改密码错误!");
//              return (actionMapping.findForward("unknown-error"));
            }
    }     public void downloadArtifact(HttpServletRequest request, HttpServletResponse response)
              throws Exception {
            Exception ex=null;
            String fileId = (String)request.getParameter("ID");
            String realFile = null;
            String realFileName = "";
            File uploadDir = new File("D:\\upload");
            if (uploadDir.isDirectory()) {
                    File[] files = uploadDir.listFiles();
                    for (int j = 0; j < files.length; j++) {
                            File tempFile = files[j];
                            if ((tempFile.getName().indexOf(fileId)) >= 0){
                                    //System.err.println("get The file" + tempFile.getName());
                                    realFile = tempFile.getName();
                                    break;
                            }
                    }
            }
            int seperatePos = realFile.lastIndexOf(".");
            String fileAppendix = realFile.substring(seperatePos+1);
            String tempFileName = realFile.substring(0,seperatePos);
            int idIndex = tempFileName.lastIndexOf(fileId);
            realFileName = tempFileName.substring(0,idIndex) + "." + fileAppendix;            realFile = "emCnGoList.xls";  //add by ander  rewrite the realFile            File file = new File("D:\\upload", realFile);
            if(!file.exists()) throw new Exception("Sorry, File Not Found");
            int length=(new Long(file.length())).intValue();
            response.setContentType("application/octet-stream; charset=UTF-8");
            response.setHeader("Content-disposition", "attachment; filename=\""+realFileName+"\"");
            //response.setHeader("Content-disposition", "attachment; filename=\""+file.getName()+"\"");
            //System.err.println("******" + realFileName);
            int bufferSize=1024;
            BufferedOutputStream output = null;
            BufferedInputStream input = null;
            output = new BufferedOutputStream(response.getOutputStream());
            input = new BufferedInputStream(new FileInputStream(file));
            try {
              int once = 0;
              int total = 0;
              byte[] buffer = new byte[bufferSize];
              do {
                once = input.read(buffer);
                total += once;
                if (once >= 0)
                  output.write(buffer, 0, bufferSize);
                }
                while ( (total < length) && (once >= 0));
                  response.flushBuffer();
                }
                catch (Exception e) {
                  ex = e;
                } // maybe user cancelled download
                finally {
                  if (input != null) input.close();
                  if(output!=null) output.close();
                  if(null!=ex) throw ex;
                }
    }
//Process the HTTP Post request
  public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doGet(request, response);
  }
}

Answer 3

<form action="download" ...>把“/download”前面的“/”去掉，可能是路径影射问题