java - 在没有大量 if else 的情况下将 VBA 条件 Switch 转换为 Java

Question

我正在尝试转换 Excel VBA代码到 Java .由于 Java 的 switch 不接受条件大小写，我很困惑如何在没有一堆 if else 的情况下编写优雅的代码。陈述。

我拥有的 VBA 代码。

           Select Case a
                Case Is < 12
                    b = (3000 + c) * 1.1
                Case 12
                    b = 4000 + c
                Case Is < 18
                    b = (4000 + c) * 1.1
                Case 18
                    b = 4500 + c
                Case Is < 24
                    b = (4500 + c) * 1.1
                Case 24
                    b = 5000 + c
                Case Is < 30
                    b = (5000 + c) * 1.1
                Case 30
                    b = 5500 + c
                Case Is < 36
                    b = (5500 + c) * 1.1
                Case 36
                    b = 6000 + c
            End Select

我不想最终用 Java 编写的代码。

    if(a<12)
        b = (3000 + c) * 1.1;
    if(a==12 )
        b = 4000 + c;
    if(a<18)
        b = (4000 + c) * 1.1;
     .
     .
     .
     .
     .

有没有更好的解决方案？任何建议和实现表示赞赏。

Answer 1

原始代码有不必要的重复，因此，您不应尝试按原样复制它。或者，如果您想这样做，您需要使用冗长的 if-else Java 中的阻塞，你想避免(并且应该)。

相反，我认为您应该分析底层(业务)逻辑并相应地进行重构。

就像是:

// assumes the given integer values are positive
public static double calculate(int a, int c) {
    final double coefficient = 1.1;
    final int multiplier = 6;
    final int increment = 500;
    final int baseValue = 3000;

    if (a < 12) {
        return (baseValue + c) * coefficient;
    }

    if (a <= 36) {
         // int division is truncated to nearest int value
        int result = ((a / multiplier) * increment) + baseValue + c;
        if (a % multiplier == 0) {
            return result;
        } else {
            return result * coefficient;
        }
    }
    throw new IllegalArgumentException("Invalid value for a (" + a + ")");
}

代码的测试运行:

public static void main(String... args) {
        final int c = 100;
        for (int a = 1; a < 37; a++) {
            System.out.println("calculate a:[" + a + "] for c:[" + c + "]. Result: [" + String.format("%.2f", calculate(a, c)) + "]");
        }
    }

控制台输出:

calculate a:[1] for c:[100]. Result: [3410,00]
calculate a:[2] for c:[100]. Result: [3410,00]
calculate a:[3] for c:[100]. Result: [3410,00]
calculate a:[4] for c:[100]. Result: [3410,00]
calculate a:[5] for c:[100]. Result: [3410,00]
calculate a:[6] for c:[100]. Result: [3410,00]
calculate a:[7] for c:[100]. Result: [3410,00]
calculate a:[8] for c:[100]. Result: [3410,00]
calculate a:[9] for c:[100]. Result: [3410,00]
calculate a:[10] for c:[100]. Result: [3410,00]
calculate a:[11] for c:[100]. Result: [3410,00]
calculate a:[12] for c:[100]. Result: [4100,00]
calculate a:[13] for c:[100]. Result: [4510,00]
calculate a:[14] for c:[100]. Result: [4510,00]
calculate a:[15] for c:[100]. Result: [4510,00]
calculate a:[16] for c:[100]. Result: [4510,00]
calculate a:[17] for c:[100]. Result: [4510,00]
calculate a:[18] for c:[100]. Result: [4600,00]
calculate a:[19] for c:[100]. Result: [5060,00]
calculate a:[20] for c:[100]. Result: [5060,00]
calculate a:[21] for c:[100]. Result: [5060,00]
calculate a:[22] for c:[100]. Result: [5060,00]
calculate a:[23] for c:[100]. Result: [5060,00]
calculate a:[24] for c:[100]. Result: [5100,00]
calculate a:[25] for c:[100]. Result: [5610,00]
calculate a:[26] for c:[100]. Result: [5610,00]
calculate a:[27] for c:[100]. Result: [5610,00]
calculate a:[28] for c:[100]. Result: [5610,00]
calculate a:[29] for c:[100]. Result: [5610,00]
calculate a:[30] for c:[100]. Result: [5600,00]
calculate a:[31] for c:[100]. Result: [6160,00]
calculate a:[32] for c:[100]. Result: [6160,00]
calculate a:[33] for c:[100]. Result: [6160,00]
calculate a:[34] for c:[100]. Result: [6160,00]
calculate a:[35] for c:[100]. Result: [6160,00]
calculate a:[36] for c:[100]. Result: [6100,00]