其實沒那麼糟糕
只是你等的人還沒到
內心的山川河流
你都已經備好
只等大雁迴歸
在屋檐下築個巢
- 方式一,非Spring環境,純JAVA類
public void download(String href, HttpServletRequest request, HttpServletResponse response) throws Exception {
String fileName = href.substring(href.lastIndexOf('/') + 1);
//url
String notesUrl = href;
//下載文件名稱
String notesName =fileName;
ServletOutputStream out = null;
InputStream inputStream = null;
try {
//文件名
String pdfName = notesName ;
//路徑
String path = notesUrl ;
// 獲取外部文件流
//logger.info("下載中------invPdfUrl=" +path);
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(3 * 1000);
//防止屏蔽程序抓取而返回403錯誤
conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
inputStream = conn.getInputStream();
/**
* 輸出文件到瀏覽器
*/
int len = 0;
// 輸出 下載的響應頭,如果下載的文件是中文名,文件名需要經過url編碼
response.setContentType("text/html;charset=utf-8");
response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(pdfName, "UTF-8"));
response.setHeader("Cache-Control", "no-cache");
out = response.getOutputStream();
byte[] buffer = new byte[1024];
while ((len = inputStream.read(buffer)) > 0) {
out.write(buffer, 0, len);
}
out.flush();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (Exception e) {
}
}
if (out != null) {
try {
out.close();
} catch (Exception e) {
}
}
}
}
- 方式二,Spring環境,使用Spring 封裝的工具類
public void download(String url, HttpServletResponse response){
InputStream is=null;
ServletOutputStream outputStream=null;
try {
URL httpUrl = new URL(url);
URLConnection con = httpUrl.openConnection();
is = con.getInputStream();
outputStream = response.getOutputStream();
//生成文件名
String suffix = url.substring(url.lastIndexOf("."));
String fileName = UUID.randomUUID()+suffix;
System.out.println(fileName);
//設置響應頭,attachment表示以附件的形式下載,inline表示在線打開
response.setHeader("content-disposition","attachment;fileName="+fileName);//下載時瀏覽器顯示的名稱
FileCopyUtils.copy(is,outputStream);
} catch (Exception e) {
e.printStackTrace();
}finally {
if (is!=null){
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (outputStream!=null){
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
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