Javaweb Servlet 下载文件_狍子的情书的博客

JavaWeb Servlet 实现下载文件

Servlet类

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URLEncoder;

/**
* Servlet下载文件
* */
public class FileSevrlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 1. 要获取下载文件的路径‘
        String filepath  = "D:\footballPicture\足球图片.jpg";
        // 2. 设置下载的文件名
        String filename = filepath.substring(filepath.lastIndexOf("\")+1);
        // 3. 设置想办法让浏览器支持下载我们需要的东西,同时要设置支持文件名中文
        resp.setHeader("Content-Disposition","attachment;filename="+ URLEncoder.encode(filename,"UTF-8"));
        // 4. 获取下载文件的输入流
        FileInputStream in = new FileInputStream(filepath);
        // 5. 创建缓冲区
        int len=0;
        byte[] buffer = new byte[1024];
        // 6. 获取OutputStream对象
        ServletOutputStream out = resp.getOutputStream();
        // 7. 将FileInputStream流写入buffer缓冲区，使用OutputStream将缓冲区中的数据输出到客户端
        while((len= in.read(buffer))>0){
            out.write(buffer,0,len);

        }
        out.flush();
        in.close();
        out.close();
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }


}

import