title: Determining filetype of file in assets folder
body: <p>Question: How do you programmatically distinguish between directories and regular files in the assets folder?</p>
  
  <p>When using AssetManager to access files in the assets folder, it seems impossible to determine if a file is in fact a file or a directory. You get the list of files from the <code>list</code> method and then open the file using the <code>open</code> method. I thought perhaps using the <code>openFd</code> method to get the asset file descriptor (and then subsequently requesting the normal file descriptor) would provide me some information. But requesting the file descriptor for a directory results in an IOException (which makes sense since what would it mean for a directory to have a file descriptor...?). </p>
  
  <p>Currently I'm relying on that IOException (resulting from attemptng to open a directory in the assets folder) in order to determine if a file is in fact a directory. (Opening a regular file works just fine). This seems like a bad idea. Any other suggestions to distinguish between a file and a directory?</p>