question: public static String createFilePath ( File cacheDir , String key ) { try { return cacheDir . getAbsolutePath ( ) + File . separator + CACHE_FILENAME_PREFIX + URLEncoder . encode ( key . replace ( "*" , "" ) , "UTF-8" ) ; } catch ( final UnsupportedEncodingException e ) { Log . e ( TAG , "createFilePath - " + e ) ; } return null ; }
target:  Creates a constant cache file mPath given a target cache directory and an image key.