从税表计算所得税

Question

用户从 UI 输入税单。然后将税单存储在数据库中。之后从数据库中取出来计算用户的所得税。

@Getter
@Setter
public class TaxSlabDto {

private String maritalStatus;
private int lowerLimit;
private int upperLimit;
private double percent;

public TaxSlabDto(String maritalStatus, int lowerLimit, int upperLimit, double percent) {
    this.maritalStatus = maritalStatus;
    this.lowerLimit = lowerLimit;
    this.upperLimit = upperLimit;
    this.percent = percent;
 }    
}

以下代码是不完整的代码。我想让它完成。我们必须用列表 taxSlabDtos 的值替换下面代码中的静态值（上限、下限、税收百分比）。

public static void main(String[] args) {
    List<TaxSlabDto> taxSlabDtos = new ArrayList();
    taxSlabDtos.add(new TaxSlabDto("Un Married", 0, 400000, 1));
    taxSlabDtos.add(new TaxSlabDto("Un Married", 400001, 500000, 10));
    taxSlabDtos.add(new TaxSlabDto("Un Married", 500001, 700000, 20));
    taxSlabDtos.add(new TaxSlabDto("Un Married", 700001, 2000000, 30));
    taxSlabDtos.add(new TaxSlabDto("Un Married", 2000000, 1000000000, 36));
    double tax = 0, income;
    Scanner sc = new Scanner(System.in);
    System.out.println("Enter income ");
    income = sc.nextDouble();
    for (TaxSlabDto taxSlabDto : taxSlabDtos) {
        if (income <= 400000) {
            tax = 1/100 * income;
        } else if (income <= 500000) {
            tax = (10/100 * (income - 400000)) + (1/100 * 400000);
        } else if (income <= 700000) {
            tax = (20/100 * (income - 500000)) + ((500000 - 400000) * 10/100) + (1/100 * 400000);
        } else if (income <= 2000000) {
            tax = ((income - 700000) * 30/100) + (20/100 * (700000 - 500000)) + ((500000 - 400000) * 10/100) + (1/100 * 400000);
        } else {
            tax = ((income - 2000000) * 36/100) + ((2000000 - 700000) * 30/100) + (20/100 * (700000 - 500000)) + ((500000 - 400000) * 10/100) + (1/100 * 400000);
        }
    }

    System.out.println("Total Income Tax " + tax);
}

目前税收计算不是动态的。这里有哪位Java Genius，可以帮我根据list taxSlabDtos 的值动态计算所得税。

Answer 1

public double calculateIncomeTax(List<TaxSlabDto> taxSlabDtos, double taxableSalary) {
    double tax = 0.0;
    for (TaxSlabDto taxSlabDtoOuter : taxSlabDtos) {
        for (TaxSlabDto taxSlabDto : taxSlabDtos) {
            Map<String, Double> map = calculateTax(taxableSalary, taxSlabDto);
            taxableSalary = map.get("Income");
            tax = tax + map.get("Tax");
            double flagValue = map.get("Flag");
            if (flagValue > 0) {
                break;
            }
        }
        if (taxableSalary == 0) {
            break;
        }
    }
    return tax;
}

private static Map<String, Double> calculateTax(Double taxableSalary, TaxSlabDto taxSlabDto) {
    Double tax = 0.0;
    Boolean flag = false;
    Map<String, Double> map = new HashMap<>();
    if (taxableSalary <= taxSlabDto.getUpperLimit()) {
        tax = calculateTax(taxSlabDto, taxableSalary);
        taxableSalary = remainingIncome(taxableSalary, taxSlabDto);
        flag = true;
    }
    map.put("Tax", tax);
    map.put("Income", taxableSalary);
    if (flag) {
        map.put("Flag", 1.0);
    } else {
        map.put("Flag", 0.0);
    }
    return map;
}

private static Double remainingIncome(Double taxableSalary, TaxSlabDto taxSlabDto) {
    if (taxSlabDto.getLowerLimit() == 0) {
        taxableSalary = taxableSalary - (taxableSalary - taxSlabDto.getLowerLimit());
    } else {
        taxableSalary = taxableSalary - (taxableSalary - taxSlabDto.getLowerLimit() + 1);
    }
    return taxableSalary;
}

private static Double calculateTax(TaxSlabDto taxSlabDto, Double taxableSalary) {
    Double tax;
    if (taxSlabDto.getLowerLimit() == 0) {
        tax = (taxSlabDto.getPercent() / 100 * (taxableSalary - (taxSlabDto.getLowerLimit())));
    } else {
        tax = (taxSlabDto.getPercent() / 100 * (taxableSalary - (taxSlabDto.getLowerLimit() - 1)));
    }
    return tax;
}