Switch case for two INT variables

Question

Consider the following code :

if (xPoint > 0 && yPoint > 0) {
    m_navigations = Directions.SouthEast;
}
else if (xPoint > 0 && yP         


        

Answer 1

The simplest and easiest solution is to use multidimensional arrays.

public class CalculateDirections {
    private final static Directions DIRECTION_MAP[][] = {
        {Directions.NorthWest, Directions.North, Directions.NorthEast},
        {Directions.West, null, Directions.East},
        {Directions.SouthWest, Directions.South, Directions.SouthEast},
    };

    public static void main(String[] args) {
        int x = Integer.valueOf(args[0]);
        int y = Integer.valueOf(args[1]);

        int signumX = Integer.signum(x);
        int signumY = Integer.signum(y);
        Directions direction = DIRECTION_MAP[signumY + 1][signumX + 1];

        System.out.println(direction);
    }
}

enum Directions {
    SouthEast, NorthEast, SouthWest, NorthWest, North, South, East, West
}

There are several advantages:

• No if/else cascades which take some runtime and are hard to manage.
• No creation of temporary Strings. In a tight game loop this may be important.
• No linear search through lists or arrays.