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    <p>You have a 'Java' tag, so assuming this is in fact Java friendly, I'd do it with an Enum:</p> <pre><code>enum USStates { TEXAS(TX_RATE), OHIO(OH_RATE), MAINE(MN_RATE), OTHER(1); final double rate; USStates(double rate) { this.rate = rate; } public double calc(double base) { double amt = amt(base); return 2.0 * basis(amt) + extra(amt) * 1.05; } public double amt(double base) { return base * rate; } } </code></pre> <p>Then, in your actual executable code:</p> <pre><code> rate = state.rate; amt = state.amt(base); calc = state.calc(base); if (USStates.OHIO == state) { points = 2; } </code></pre> <p>If "base" is a constant (that wasn't clear from the example code) this can be simplified further by accessing it directly as a final rather than passing it in as a parameter.</p> <p>This solution has a few benefits. Firstly, the actual rates for a state do not actually need to be in their own separate constant using a naming convention, but can actually be stored as part of the Enum itself (so instead of "TEXAS(TX_RATE)" you could actually just enter "TEXAS(1.4)" (or whatever its value is)) and the rate is then maintained as part of the "TEXAS" enumerated type.</p> <p>It also has the benefit that the calculation logic is captured (encapsulated, even) along with the constants it operates on.</p> <p>By using Enums, you ensure that people can't accidentally use invalid operations on your constants (like accidentally performing mathematical operations on them).</p> <p>By reducing the number of conditional statements, you significantly reduce the number of possible execution paths. Fewer possible paths means fewer possibilities for null pointers and uninitialized variables. (As the sample code stands, there's a risk of an uninitialized variable error in "points" for any states other than OHIO)</p>
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    1. COI would suggest putting points in the enum so any points can be applied to any state in the future.
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      1. USPaul
    2. CO@Paul, the problem with having points in the enum is that it's undefined for all enums *except* Ohio. If it is in the enum, then all other states would need a value (possibly null). In the original snippet, points is only modified for Ohio, so if it had a value *before* the snippet, it would still have that value *after* the snippet. If I add "int points()" to the enum, then for other states the original value would be overwritten by the default. (Thus my 'uninitialized variables' comment above). As I'm not sure what's happening before/after the code, I'm playing it safe.
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    3. COfair enough :) you make a good case
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