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标题:
download servlet
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作者:
这个好吃给你吃
时间:
2019-5-9 13:48
标题:
download servlet
package cn.itcast.servlet;
import cn.itcast.utils.DownLoadUtils;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
@WebServlet("/dkservlet")
public class dkservlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1. 获取文件名称
String filename = request.getParameter("filename");
//2. 使用字节输入流加载文件进内存
ServletContext servletContext = this.getServletContext();
String realPath = servletContext.getRealPath("/img/"+filename);
FileInputStream fis = new FileInputStream(realPath);
System.out.println(realPath);
//3. 指定response的响应头: content-disposition:attachment;filename=xxx
String mp = servletContext.getMimeType(filename);
//3.1 制定响应头对应的浏览器解析的content-Type
response.setHeader("content-Type",mp);
//3.1.1 解决中文乱码问题
String agent = request.getHeader("user-agent");
//3.1.2 调用工具类
filename = DownLoadUtils.getFileName(agent, filename);
//3.2 设置响应头
response.setHeader("content-disposition","attachment;filename="+filename);
//4.将数据写出到response输出流
ServletOutputStream sos = response.getOutputStream();
byte[] bs = new byte[1024 * 8];
int len = 0;
while ((len = fis.read(bs))!= -1 ){
sos.write(bs,0,len);
}
fis.close();
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
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