用jsp实现文件的下载（download.jsp）

------------------------------------------------download.jsp代码如下----------------------------------------------

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ page import="java.io.*,java.util.*"%>
<%!
public static final String TEXT_CSS = "text/css";
public static final String TEXT_HTML = "text/html";
public static final String TEXT_PLAIN = "text/plain";
public static final String TEXT_RICHTEXT = "text/richtext";
public static final String TEXT_RTF = "text/rtf";
public static final String TEXT_SGML = "text/sgml";
public static final String TEXT_XML = "text/xml";

public static final String IMAGE_CGM = "image/cgm";
public static final String IMAGE_GIF = "image/gif";
public static final String IMAGE_JPEG = "image/jpeg";
public static final String IMAGE_PNG = "image/png";
public static final String IMAGE_TIFF = "image/tiff";

public static final String VIDIO_MPEG = "vidio_mpeg";

public static final String MODEL_VRML = "model/vrml";
public static final String MODEL_IGES = "model/iges";
public static final String MODEL_MESH = "model/mesh";

public static final String APPLICATION_OCTET_STREAM = "application/octet-stream";
public static final String APPLICATION_JAVA = "application/java";
public static final String APPLICATION_POSTSCRIPT = "application/postscript";
public static final String APPLICATION_PDF = "application/pdf";
public static final String APPLICATION_ZIP = "application/zip";
public static final String APPLICATION_MSWORD = "application/msword";
public static final String APPLICATION_MSEXCEL = "application/vnd.ms-excel";
public static final String APPLICATION_XML = "application/xml";

private static List resContList = null;
/**  
 * 功能：对文件类型进行初始化  
 */
static {

     resContList = new ArrayList();
     resContList.add(TEXT_CSS);
     resContList.add(TEXT_HTML);
     resContList.add(TEXT_PLAIN);
     resContList.add(TEXT_RICHTEXT);
     resContList.add(TEXT_RTF);
     resContList.add(TEXT_SGML);
     resContList.add(TEXT_XML);
     resContList.add(IMAGE_CGM);
     resContList.add(IMAGE_GIF);
     resContList.add(IMAGE_JPEG);
     resContList.add(IMAGE_PNG);
     resContList.add(IMAGE_TIFF);
     resContList.add(VIDIO_MPEG);
     resContList.add(MODEL_VRML);
     resContList.add(MODEL_IGES);
     resContList.add(MODEL_MESH);
     resContList.add(APPLICATION_OCTET_STREAM);
     resContList.add(APPLICATION_JAVA);
     resContList.add(APPLICATION_POSTSCRIPT);
     resContList.add(APPLICATION_PDF);
     resContList.add(APPLICATION_ZIP);
     resContList.add(APPLICATION_MSWORD);
     resContList.add(APPLICATION_MSEXCEL);
     resContList.add(APPLICATION_XML);
}

 

/**
 * 功能：获取文件类型
 */
static String getContentType(String fileName) {
     String contentType = "application/x-msdownload";
     if (fileName.indexOf(".") > -1) {
          String fileType = fileName.substring(fileName.lastIndexOf(".") + 1);
          int size = resContList.size();
          String contTypeName = "";
          fileType = fileType.toLowerCase();
          for (int i = 0; i < size; i++) {
               contTypeName = (String) resContList.get(i);
               if(contTypeName.indexOf(fileType) > -1) {
                    contentType = contTypeName;
                    break;
               }
          }
     }
     return contentType;
}
%>
<%
out.clear();
out = pageContext.pushBody();

 

//要下载的文件路径  如："D:/fileload/"
String filePath = this.getServletContext().getRealPath(request.getParameter("path")) + "//";  
String fileName = new String(request.getParameter("name").getBytes("iso-8859-1"), "UTF-8");       //要下载的文件名  如："test.doc"
FileInputStream fis = null;                                      //输入流
ServletOutputStream sos = null;                             //输出流 

try {
     //File file = new File(filePath, fileName);
     response.setContentType(getContentType(fileName)+ "; charset=UTF-8");
     response.setHeader("Content-disposition","attachment; filename=" + new String(fileName.getBytes("UTF-8"),"iso8859-1"));

     fis = new FileInputStream(filePath + fileName); //读入文件
     sos = response.getOutputStream();
     sos.flush();
     int aRead = 0;
     while ((aRead = fis.read()) != -1 & fis != null) {
          sos.write(aRead);
     }
     sos.flush();
} catch (Throwable e) {
} finally {
     try {
          fis.close();
          sos.close();
     } catch (Throwable e){
     }
}
%>

-----------------------------------------------------调用如下---------------------------------------------------

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