Java下载Servlet Demo

request.setCharacterEncoding("utf-8");
        String name=request.getParameter("name");
        //1、设置响应头
        response.setContentType("application/force-download");
        //2、读取文件
        String path=getServletContext().getRealPath("/file/"+name);
        InputStream in=new FileInputStream(path);
        //3、对文件名进行编码
        name=URLEncoder.encode(name, "utf-8");
        //4、设置响应头
        response.setHeader("Content-Disposition","attachment;filename="+name);//如果不写attachment，则会在浏览器中打开
        response.setContentLength(in.available());
        //5、开始copy文件
        OutputStream out=response.getOutputStream();
        byte[] b=new byte[1024];
        int len=-1;
        while((len=in.read(b))!=-1)
        {
            out.write(b, 0, len);
        }
        out.close();
        in.close();
        
        
    }

写在Servlet中，可以防止盗链，进行过滤等操作