Html部分
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert title here</title> </head> <body> <a href="http://localhost:8080/webdemojava/download1?filename=a.flv" class="downloadbtn">a.flv</a> <a href="http://localhost:8080/webdemojava/download1?filename=a.jpg" class="downloadbtn">a.jpg</a> <a href="http://localhost:8080/webdemojava/download1?filename=a.mp3" class="downloadbtn">a.mp3</a> <a href="http://localhost:8080/webdemojava/download1?filename=a.mp4" class="downloadbtn">a.mp4</a> <a href="http://localhost:8080/webdemojava/download1?filename=a.txt" class="downloadbtn">a.txt</a> <a href="http://localhost:8080/webdemojava/download1?filename=a.z1ip" class="downloadbtn">a.z1ip</a> </body> </html>
Java代码
package action; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.net.URLEncoder; import javax.servlet.ServletException; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.jasper.tagplugins.jstl.core.Out; import sun.misc.BASE64Encoder; public class DownLoad1 extends HttpServlet { private static final long serialVersionUID = 1L; public DownLoad1() { super(); // TODO Auto-generated constructor stub } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String filename = request.getParameter("filename"); //获取发送过来的文件名 filename = new String(filename.getBytes("ISO8859-1"),"UTF-8"); //解决传过来的文件名是中文.会变乱码的问题 //获得请求头中的 User-Agent String agent = request.getHeader("User-Agent"); //根据不同的客户的 进行不同的编码 .解决下载的文件 中文 没名字 String filenameEncoder = ""; if (agent.contains("MSIE")) { // IE浏览器 filenameEncoder = URLEncoder.encode(filename, "utf-8"); filenameEncoder = filenameEncoder.replace("+", " "); } else if (agent.contains("Firefox")) { // 火狐浏览器 BASE64Encoder base64Encoder = new BASE64Encoder(); filenameEncoder = "=?utf-8?B?" + base64Encoder.encode(filename.getBytes("utf-8")) + "?="; } else { // 其它浏览器 filenameEncoder = URLEncoder.encode(filename, "utf-8"); } String realPath = this.getServletContext().getRealPath("/download/"+filename); //相对路径变绝对路径 InputStream in = null; try { in = new FileInputStream(realPath); //读到要下载的文件.并做检测文件是否存在 } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } if (in == null) { response.setContentType("text/html;charset=UTF-8"); response.getWriter().append("没有找到该文件"); return; } ServletOutputStream out = response.getOutputStream(); response.setContentType(this.getServletContext().getMimeType(filename)); //设置返回的文件类型 response.setHeader("Content-Disposition", "attachment;filename="+filenameEncoder); //告诉客户的文件以附件类型打开(下载) int len = 0; byte[] buffer = new byte[1024]; while ((len=in.read(buffer))>0) { out.write(buffer, 0, len); } in.close(); out.close(); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }