public Square getSquareAtPosition(Position position){

        int posrow = position.getrow();//ligne
        int poscolumn = position.getcolumn();//colone
        if (this.squares[posrow][poscolumn] == null) {
            throw new IllegalArgumentException("Hors du plateau");
        } else {
            return this.squares[position.getrow()][position.getcolumn()];
        }
    }