protected function getEncodeBook()
    {
        if (self::$encodeBook === null) {
            self::$encodeBook = array_flip(self::$decodeBook);
        }

        return self::$encodeBook;
    }
protected function getEncodeBook()
    {
        if (self::$encodeBook === null) {
            self::$encodeBook = array_flip(self::$decodeBook);
        }

        return self::$encodeBook;
    }
protected function getEncodeBook ( ) { if ( self :: $ encodeBook === null ) { self :: $ encodeBook = array_flip ( self :: $ decodeBook ) ; } return self :: $ encodeBook ; }
Returns the book used to encode.

@author Benjamin Carl <opensource@clickalicious.de>
@return array The encode book
@access protected
Returns the book used to encode .