多维数组：Java

Question

I am working on a tax calculator and had the idea of putting the tax brackets into a multi-dimensional array. This is the first time I have tried such a thing and was wondering if this is the correct way of doing it?

private static double[][][] taxBrackets;

static {
    taxBrackets = new double[20][14][14];
/*Single*/                           /*Married*/                        /*Head of Household*/
    //TierOne                           //TierOne                           //TierOne
    taxBrackets[0][0][0] = 0;           taxBrackets[0][1][0] = 0;           taxBrackets[0][0][1] = 0;       //MIN
    taxBrackets[1][0][0] = 9075;        taxBrackets[0][2][0] = 18150;       taxBrackets[0][0][2] = 12950;   //MAX
    taxBrackets[2][0][0] = 0.10;                                                                         //Tax Rate
    //TierTwo
    taxBrackets[3][0][0] = 9076;        taxBrackets[0][3][0] = 18151;       taxBrackets[0][0][3] = 12951;   //MIN
    taxBrackets[4][0][0] = 36900;       taxBrackets[0][4][0] = 73800;       taxBrackets[0][0][4] = 49400;   //MAX
    taxBrackets[5][0][0] = 0.15;                                                                         //Tax Rate
    //TierThree
    taxBrackets[6][0][0] = 36901;       taxBrackets[0][5][0] = 73801;       taxBrackets[0][0][5] = 49401;   //MIN
    taxBrackets[7][0][0] = 89350;       taxBrackets[0][6][0] = 148850;      taxBrackets[0][0][6] = 127550;  //MAX
    taxBrackets[8][0][0] = 0.25;                                                                         //Tax Rate
    //TierFour
    taxBrackets[9][0][0] = 89351;       taxBrackets[0][7][0] = 148851;      taxBrackets[0][0][7] = 127551;  //MIN
    taxBrackets[10][0][0] = 186350;     taxBrackets[0][8][0] = 226850;      taxBrackets[0][0][8] = 206600;  //MAX
    taxBrackets[11][0][0] = 0.28;                                                                        //Tax Rate
    //TierFive
    taxBrackets[12][0][0] = 186351;     taxBrackets[0][9][0] = 226851;      taxBrackets[0][0][9] = 206601;  //MIN
    taxBrackets[13][0][0] = 405100;     taxBrackets[0][10][0] = 405100;     taxBrackets[0][0][10] = 405100; //MAX
    taxBrackets[14][0][0] = 0.33;                                                                        //Tax Rate
    //TierSix
    taxBrackets[15][0][0] = 405101;     taxBrackets[0][11][0] = 405101;     taxBrackets[0][0][11] = 405101; //MIN
    taxBrackets[16][0][0] = 406750;     taxBrackets[0][12][0] = 457600;     taxBrackets[0][0][12] = 432200; //MAX
    taxBrackets[17][0][0] = 0.35;                                                                        //Tax Rate
    //TierSeven
    taxBrackets[18][0][0] = 406751;      taxBrackets[0][13][0] = 457601;     taxBrackets[0][0][13] = 432201; //MIN
    taxBrackets[19][0][0] = 0.396;                                                                       //Tax Rate
}

The idea was to have Single filers in the left array, Married/Joint filers in the middle and Head of Household filers in the right array. Did I do this correctly or did I miss the point entirely?

UPDATE: 1/30/2017 After following Nhouser9's suggestions I ended up with this which is much more manageable.

private static class TaxBracket {

    final double minSalary;
    final double maxSalary;
    final double taxRate;

    TaxBracket(double minSalary, double maxSalary, double taxRate) {
        this.minSalary = minSalary;
        this.maxSalary = maxSalary;
        this.taxRate = taxRate;
    }
}
//This is the data structure which holds the values for each tier of each filing status
//Changing values in these arrays will affect the output of the entire program
private static TaxBracket[] singleFiler;
static {
    singleFiler = new TaxBracket[]
        {
            new TaxBracket(0, 9075, 0.10),      //Index 0 TierOne
            new TaxBracket(9076, 36900, 0.15),  //Index 1 TierTwo
            new TaxBracket(36901, 89350, 0.25), //Index 2 TierThree
            new TaxBracket(89351, 186350, 0.28),//Index 3 TierFour
            new TaxBracket(186351, 405100, 0.33),//Index 4 TierFive
            new TaxBracket(405101, 406750, 0.35),//Index 5 TierSix
            new TaxBracket(406751, Double.MAX_VALUE, 0.396)//Index 6 TierSeven
        };
}
private static TaxBracket[] jointFiler;
static {
    jointFiler = new TaxBracket[]
        {
            new TaxBracket(0, 18150, 0.10),      //Index 0 TierOne
            new TaxBracket(18151, 73800, 0.15),  //Index 1 TierTow
            new TaxBracket(73801, 148850, 0.25), //Index 2 TierThree
            new TaxBracket(148851, 226850, 0.28),//Index 3 TierFour
            new TaxBracket(226851, 405100, 0.33),//Index 4 TierFive
            new TaxBracket(405101, 457600, 0.35),//Index 5 TierSix
            new TaxBracket(457601, Double.MAX_VALUE, 0.396)//Index 6 TierSeven
        };
}
private static TaxBracket[] hohFiler;
static {
    hohFiler = new TaxBracket[]
        {
            new TaxBracket(0, 12950, 0.10),      //Index 0 TierOne
            new TaxBracket(12951, 49400, 0.15),  //Index 1 TierTow
            new TaxBracket(49401, 127550, 0.25), //Index 2 TierThree
            new TaxBracket(127551, 206600, 0.28),//Index 3 TierFour
            new TaxBracket(206601, 405100, 0.33),//Index 4 TierFive
            new TaxBracket(405101, 432200, 0.35),//Index 5 TierSix
            new TaxBracket(432201, Double.MAX_VALUE, 0.396)//Index 6 TierSeven
        };
}

Answer 1

This is one possible solution. If it works, it's fine.

Since Java is an Object Oriented language, It would be better to use Objects. For example, TaxBracket object like this:

public class TaxBracket {
    public static final int SINGLE = 1;
    public static final int MARRIED = 2;
    public static final int HEAD_OF_HOUSE = 3;

    public final int mStatus;
    public final int minSalary;
    public final int maxSalary;
    public final double rate;

    public TaxBracket(int mStatus, int minSalary, int maxSalary, double rate) {
        this.mStatus = mStatus;
        this.minSalary = minSalary;
        this.maxSalary = maxSalary;
        this.taxRate = taxRate;
    }
}

Then instead of multi-dimensional arrays you could declare a single array of these objects, initializing it like this:

taxBrackets[0] = new TaxBracket(TaxBracket.SINGLE, 0, 9075, .1);

Answer 2

No. It is not the best way to do that. I would implement three classes for Single , Married and HeadOfHousehold .

Each of this class would implement an interface, eg Married implements TaxTiers .

interface TaxTiers() {

  public int getMaxForTier(int tier) {
  }

  public int getMinForTier(int tier) {
  }

  public double getRateForTier(int tier) {
  }
}

In classes Single , Married and HeadOfHousehold you can have 3 arrays or List s: tierMins , tierMaxs and tierRates . Then you just write:

public double getRateForTier(int tier) {
  return tierRates.get(tier);
}

Answer 3

I would prefer to create a class for the tax bracket contains the attributes Single , Married , HeadOfHousehold and all other attributes you have. And, initiate a single dimension array of instances of that class. Like the following:

class TaxBracket{
    double single;
    double married;
    double headOfHousehold;

    .... // any other attributes + getters and setters! 

}

In the main class, you define the array:

TaxBracket []taxBrackets = new TaxBracket[20];