Double到BigDecimal Java

Question

将所有这些双精度值更改为BigDecimal的最佳方法是什么？我想我开始时没有意识到我应该将BigDecimal用于基于财务的程序。我对Java很陌生，感谢任何反馈。

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;
    }
}
private static TaxBracket[] singleFiler;
static {
    singleFiler = new TaxBracket[]
        {
            new TaxBracket(0.0, 9075.0, 0.10),      //Index 0 TierOne
            new TaxBracket(9076.0, 36900.0, 0.15),  //Index 1 TierTwo
            new TaxBracket(36901.0, 89350.0, 0.25), //Index 2 TierThree
            new TaxBracket(89351.0, 186350.0, 0.28),//Index 3 TierFour
            new TaxBracket(186351.0, 405100.0, 0.33),//Index 4 TierFive
            new TaxBracket(405101.0, 406750.0, 0.35),//Index 5 TierSix
            new TaxBracket(406751.0, Double.MAX_VALUE, 0.396)//Index 6 TierSeven
        };
}
private static TaxBracket[] jointFiler;
static {
    jointFiler = new TaxBracket[]
        {
            new TaxBracket(0.0, 18150.0, 0.10),      //Index 0 TierOne
            new TaxBracket(18151.0, 73800.0, 0.15),  //Index 1 TierTow
            new TaxBracket(73801.0, 148850.0, 0.25), //Index 2 TierThree
            new TaxBracket(148851.0, 226850.0, 0.28),//Index 3 TierFour
            new TaxBracket(226851.0, 405100.0, 0.33),//Index 4 TierFive
            new TaxBracket(405101.0, 457600.0, 0.35),//Index 5 TierSix
            new TaxBracket(457601.0, Double.MAX_VALUE, 0.396)//Index 6 TierSeven
        };
}
private static TaxBracket[] hohFiler;
static {
    hohFiler = new TaxBracket[]
        {
            new TaxBracket(0.0, 12950.0, 0.10),      //Index 0 TierOne
            new TaxBracket(12951.0, 49400.0, 0.15),  //Index 1 TierTow
            new TaxBracket(49401.0, 127550.0, 0.25), //Index 2 TierThree
            new TaxBracket(127551.0, 206600.0, 0.28),//Index 3 TierFour
            new TaxBracket(206601.0, 405100.0, 0.33),//Index 4 TierFive
            new TaxBracket(405101.0, 432200.0, 0.35),//Index 5 TierSix
            new TaxBracket(432201.0, Double.MAX_VALUE, 0.396)//Index 6 TierSeven
        };

Answer 1

你应该：

1. 将所有受影响的double更改为BigDecimal。
2. 更改new TaxBracket(...)的参数，例如始终9075.0到new BigDecimal("9075.0")。注意引号。如果你没有引用你所获得的价值，那就不会解决任何问题。

或者你可以将构造函数参数更改为String并在构造函数中执行new BigDecimal(...)，这可能更整洁。

Answer 2

您可以这样做（如果您想将双值保留为输入）：

void changeToBigDecimal(){
    BigDecimal minSalaryDec = new BigDecimal(this.minSalary, MathContext.DECIMAL64);
    BigDecimal maxSalaryDec = new BigDecimal(this.maxSalary, MathContext.DECIMAL64);
    BigDecimal taxRateDec= new BigDecimal(this.taxRate, MathContext.DECIMAL64);
}

在构造函数中设置初始值后调用它。如果你愿意，你也可以把它们变成全局变量而不是本地变量。

Answer 3

我建议您将TaxBracket类顶部的3个双变量更改为BigDecimals。在TaxBracket的构造函数中，使用BigDecimal constructor that takes a double

当你完成时，它应该看起来像这样：

private static class TaxBracket {

final BigDecimal minSalary;
final BigDecimal maxSalary;
final BigDecimal taxRate;

TaxBracket(double minSalary, double maxSalary, double taxRate) {
    this.minSalary = new BigDecimal(minSalary);
    this.maxSalary = new BigDecimal(maxSalary );
    this.taxRate = new BigDecimal(taxRate );
}