code: @SuppressWarnings("resource")
      public InputStream getInputStream(String filename)
      {
          InputStream streamIn = null;
          if (filename.indexOf(':') == -1)
          {
              String filepath = ((BaseHttpTask)this.getTask()).getRealPath(this.getServletRequest(), filename);
              if (filepath != null)
              {
  	            File file = new File(filepath);
  	            try   {
  	                streamIn = new FileInputStream(file);
  	            } catch (FileNotFoundException ex)  {
  	                streamIn = null;
  	            }
              }
          }
          if (streamIn == null)
              streamIn = Utility.getInputStream(filename, this.getApplication());
          return streamIn;
      }
docs: A utility method to get an Input stream from a filename or URL string.
  @param filename The filename or url to open as an Input Stream.
  @return The imput stream (or null if there was an error).