java - Width and height information of uploaded image through servlet -


i'm new java servlets , stackoverflow. need store image in database blob-object. image must 300x300px , have size less 400kb. image uploaded html-form.

this code have far:

protected void dopost(httpservletrequest request, httpservletresponse response)         throws servletexception, ioexception {     request.setcharacterencoding("utf-8");     response.setcontenttype("text/html;charset=utf-8");      final printwriter writer = response.getwriter();     final part filepart = request.getpart("albumthumbnail");      imageinfo ii = new imageinfo();      ii.setinput(filepart.getinputstream());      if(filepart != null){         writer.println(ii.getformatname());         writer.println(ii.getheight());         writer.println(ii.getwidth());         writer.println("ok");         writer.println(filepart.getname());         writer.println(filepart.getsize());         writer.println(filepart.getcontenttype());     }

when upload file output:

jpeg 0 0 ok albumthumbnail 1421773 image/png

it looks imageinfo class using default values instead of image parameters because uploaded png-file.

i don't know if right obtain width , height of uploaded image. better solutions welcome, thanks.


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