java 下载网络图片输入到浏览器进行下载

进行下载"/>

java 下载网络图片输入到浏览器进行下载

需求：满足用户，可以在前端下载图片，图片为网络图片

图片链接比如：.thumb.700_0.jpg

以下代码标红的地方是关键，由于是浏览器请求，输出流应该从response.getOutputStream(); 中获得

前端代码：

<a id="QrCodeDownload" href="<%=path%>/base/ssCheckPoint/downImg?src=.thumb.700_0.jpg" download="二维码"><span>下载图片</span></a>

后端代码：
 

public static void main(String[] args) throws Exception {String imgPath =".thumb.700_0.jpg";downNetWorkImgUtil(null,imgPath); //注意，此处其实不能为null，只是在main方法中给大家举例一下调用的方式，这里应该要传response
}

/*** TODO: 下载网络图片（文件流输出到浏览器弹出下载）* * @param:* @return:* @auther: mukk* @date: 2019/9/5 17:39*/
public static void downNetWorkImgUtil(HttpServletResponse response, String imgPath) throws Exception {try {URL url = new URL(imgPath);DataInputStream dataInputStream = new DataInputStream(url.openStream());OutputStream fileOutputStream = response.getOutputStream();ByteArrayOutputStream output = new ByteArrayOutputStream();response.reset();response.setContentType("application/octet-stream");response.setCharacterEncoding("UTF-8");response.setHeader("Content-disposition", "attachment; filename=" + (imgPath.substring(imgPath.lastIndexOf("/") + 1, imgPath.length())));byte[] buffer = new byte[1024];int length;while ((length = dataInputStream.read(buffer)) > 0) {output.write(buffer, 0, length);}byte[] context = output.toByteArray();fileOutputStream.write(output.toByteArray());dataInputStream.close();fileOutputStream.close();} catch (MalformedURLException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}