code: static void interceptLoadingFiles( Properties props ) throws IOException {
  
  		Logger logger = Logger.getLogger( UserDataHelpers.class.getName());
  		Set<String> keys = props.stringPropertyNames();
  		for( final String key : keys ) {
  			if( ! key.startsWith( ENCODE_FILE_CONTENT_PREFIX ))
  				continue;
  
  			String realKey = key.substring( ENCODE_FILE_CONTENT_PREFIX.length());
  			String value = props.getProperty( realKey );
  			if( value == null ) {
  				logger.fine( "No file was specified for " + realKey + ". Skipping it..." );
  				continue;
  			}
  
  			File f = new File( value );
  			if( ! f.exists())
  				throw new IOException( "File " + f + " was not found." );
  
  			// Read the file content as bytes
  			ByteArrayOutputStream os = new ByteArrayOutputStream();
  			Utils.copyStream( f, os );
  			String encodedFileContent = encodeToBase64( os.toByteArray());
  			props.put( key, encodedFileContent );
  		}
  	}
docs: Intercepts the properties and loads file contents.
  @param props non-null properties
  @throws IOException if files had to be loaded and were not found