Servlet设置实现下载文件

        实现网页下载文件的Servlet类实现

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;

public class download extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取下载路径
        String realPath="F:\Project\Java\IdeaProjects\Maven\JavaWeb-02\Servlet-01\target\classes\1.jpg";
        System.out.println("download path"+realPath);
        //获取文件名
        String filename=realPath.substring(realPath.lastIndexOf("\")+1);
        //浏览器下载支持；可设置URL编码使支持中文名文件显示
        resp.setHeader("Content-Disposition","attachment;filename="+ filename);
        //获取下载文件输入流
        FileInputStream in=new FileInputStream(realPath);
        //创建缓存区
        int len;
        byte[] buffer=new byte[1024];
        //获取resp中OutputStream对象
        ServletOutputStream out=resp.getOutputStream();
        //将FileOutputStream流写入到Buffer缓存区，使用OutputStream流将数据输出到客户端
        while((len=in.read(buffer))!=-1){
            out.write(buffer,0,len);
        }
        //关闭输入输出流
        in.close();
        out.close();
    }

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