下载(W11DownLoadServlet.java和downl
:(W11DownLoadServlet.java和downlist.jsp和Downservlet.java)中介绍
1) DownLoadServlet.java中有关遍历本地的资源,以及要转发到downlist.jsp中展示,DownServlet.java中进行下载代码的实现
1.1)DownLoadServlet.java中有关遍历本地的资源:
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stub//response.getWriter().append("Served at: ").append(request.getContextPath());//保存文件的完整名称(key)和简化名称(value)MapfileNames = new HashMap<>();
//获取目录中所有文件
String path = "D:/upload";
File dirFile = new File(path);
//没有判断文件夹的情况。
if (dirFile!=null||dirFile.isDirectory()) {
String[] list = dirFile.list();
if (list!=null&&list.length>0) {
for (int i = 0; i < list.length; i++) {
String fullName = list[i];
String shortName = fullName.substring(fullName.indexOf("-")+1);
fileNames.put(fullName, shortName);
}
}
}
request.setAttribute("fileMap", fileNames);
//通过转发调到界面
request.getRequestDispatcher("/downlist.jsp").forward(request, response);
}
1.2)转发到downlist.jsp中展示
1.3)DownServlet.java中进行下载代码的实现
:
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//response.getWriter().append("Served at: ").append(request.getContextPath());
String fileName = request.getParameter("name");
//处理get方式的中文乱码
fileName = new String(fileName.getBytes("iso-8859-1"),"utf8");
String path = "D:/upload";
//获取输入流
InputStream in = new FileInputStream(new File(path,fileName));
//对URL的处理,不处理文件名中 中文会变成“ ”等形式
fileName=URLEncoder.encode(fileName,"utf8");
//设置下载的响应头,请求的内容存为文件时,需要一个默认的文件名
response.setHeader("content-disposition", "attachment;fileName="+fileName);
//获得响应的输出流
ServletOutputStream out = response.getOutputStream();
//将输入流中的数据通过输出流进行保存
byte[] buff = new byte[1024];
int len=-1;
while ((len=in.read(buff))!=-1) {
out.write(buff,0,len);
}
out.close();
in.close();
}
注:********
//获取输入流
InputStream in = new FileInputStream(new File(path,fileName));
//对URL的处理,不处理文件名中 中文会变成“ ”等形式
fileName=URLEncoder.encode(fileName,"utf8");
//设置下载的响应头,请求的内容存为文件时,需要一个默认的文件名
response.setHeader("content-disposition", "attachment;fileName="+fileName);
//获得响应的输出流
ServletOutputStream out = response.getOutputStream();