How to show an image in JSP given the bytes[] of the photo?

Question

Hi all,
I stored a user's picture in the db as text. For this I simply converted the JPG to bytes[] and from bytes to string: Base64.encode(bytes)
Now I wish to do the reverse - to 'output' the image on the screen. So given the bytes[] of the image with
          byte[] bytesDB = Base64.decode(userPhotoStr); //userPhotoStr is something like this: /9j/4AAQSkZJRgA...Question: How can I show the image in the JSP page embedded in the page not as download?
I'm using struts with JSP pages.
Thank you!!!!

Answer 1

Images in HTML are to be displayed using <img> element. All what an <img> element can take as image is an URL pointing to the image in question.
If the image is dynamic, then you can just let that URL point to some Servlet which takes some request parameter or reads the path info, reads/gets the image as byte array or (much more efficient) as inputstream and writes it to the outputstream of the response.
You may get some ideas out of this: [http://balusc.blogspot.com/2007/04/imageservlet.html].
By the way, massaging the byte array from/to a String is a terribly bad idea. Just store bytes as computer readable bytes, not as human readable characters, this makes completely no sense. Characters on its turn have to be converted to bytes again after all, but now you've let the DB do the work. All with all a performance pain. Bytes > Chars > Bytes > Chars > Bytes instead of just Byes > Bytes. In database you normally use BLOB, BINARY or equivalent for this in combination with JDBC's PreparedStatement#setBinaryStream() and ResultSet#getBinaryStream().