java - 嵌套 if 语句遇到问题

Question

理论认为，不同收入层次的税率不同。前 5 万个 10%，接下来的 5 万个 15%，超过 10 万个 25%。

 public double getTaxesWithheld() {

    if (taxableIncome >= 100000.0) {

        taxesWitheld = taxesWitheld+ (.25 * (taxableIncome - 100000.0));
        taxableIncome = taxableIncome - 100000.0;
    } else {
        if (taxableIncome >= 50000.0 && taxableIncome <= 100000.0) {
            taxesWitheld = taxesWitheld + (.15 * (taxableIncome - 50000.0));
            taxableIncome = taxableIncome - 50000.0;
        } else {
            if (taxableIncome < 50000.0) {
                taxesWitheld = taxesWitheld + (.1 * (taxableIncome - 25000.0));
            }
        }

        if (taxableIncome <= 0) {
            return 0.0;
        }

    }
    return taxesWitheld;
}

测试用例1: @测试构造函数值(first_name、last_name、job_title、id、month_salary)

public void EmployeeMakingBetween50Kand100K() {
    Employee h = new EmployeeImpl("Jon", "Smith", "Miner", 2222, 6166.75);


    assertEquals(h.getMonthlySalary(), 6166.75, 0.005);
    assertEquals(h.getGrossYearlyIncome(), 6166.75*12, 0.005);
    assertEquals(h.getTaxableIncome(), h.getGrossYearlyIncome(), 0.005);
    assertEquals(h.getTaxesWithheld(), 8600.15, 0.005);
    assertEquals(h.getNetYearlyIncome(), h.getGrossYearlyIncome()-h.getTaxesWithheld(), 0.005);
}

不会处理taxWithheld(), 8600.15, 0.005

Answer 1

这是一种完全不同的方法，可能会产生更好的结果:

 public double getTaxesWithheld() {

    over100k = Math.max(taxableIncome-100000, 0);
    taxableIncome -= over100k;
    over50k = Math.max(taxableIncome-50000, 0);
    taxableIncome -= over50k;

    taxesWitheld = taxesWitheld + (.25 * over100k);
    taxesWitheld = taxesWitheld + (.15 * over50k);
    taxesWitheld = taxesWitheld + (.1 * taxableIncome);
    return taxesWitheld;
}