File.createTempFile() VS new File()
In my app I added the possibility to add and save pictures for everyday day, represented by a Fragment.
In order to save the picture on the SD card, I currently use the function File.createTempFile:
File imageFile = File.createTempFile(imageFileName, MyApplication.JPEG_FILE_SUFFIX, MyApplication.getAlbumDir());
I actually also tried with the standard way:
File imageFile = new File(MyApplication.getAlbumDir(), imageFileName + MyApplication.JPEG_FILE_SUFFIX);
Both are working, but in my case the first one is better than the second one because the function createTempFile adds a long random number at the end of the file name making it unique.
To give you an example, here is what I get with both methods:
With createTempFile: IMG_2013-06-18_-1961144729.jpg
With new File: IMG_2013-06-18_.jpg
Finally my question is, is it safe to keep using createTempFile to save my pictures or do I have to use the standard way and add some code to generate a unique file name? Should it only be used for temporary files?
I reviewed the documentation about the function but I did not find anything about the possible consequences of using it instead of new File.
Thank you
Answer
Sounds like your app is creating files, so you need to guarantee unique filenames. You could keep some kind of counter within your app (saved to preferences or DB) and use that. Then you could create shorter/more controlled names, and control uniqueness yourself. Or you can use createTempFile(), which will guarantee you get a unique filename (but you only get partial control of the filename). Sounds like you prefer createTempFile(), so there's no reason not to continue using it if you are happy with the filenames it generates. There's no down side other than not having full control over the filename format.