80 lines
2.1 KiB
Plaintext
80 lines
2.1 KiB
Plaintext
== Why is this an issue?
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Some mathematical operations are unnecessary and should not be performed because their results are predictable.
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For instance, `anyValue % 1` will always return 0, as any integer value can be divided by 1 without remainder.
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Similarly, casting a non-floating-point to a floating-point value and then passing it to `Math.round`, `Math.ceil`, or `Math.floor` is also unnecessary, as the result will always be the original value.
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The following operations are unnecessary when given any constant value: `Math.abs`, `Math.ceil`, `Math.floor`, `Math.rint`, `Math.round`.
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Instead, use the result of the operation directly.
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The following operations are unnecessary with certain constants and can be replaced by the result of the operation directly:
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[frame=all]
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[cols="^1,^1"]
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|===
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|Operation|Value
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|acos|0.0 or 1.0
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|asin|0.0 or 1.0
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|atan|0.0 or 1.0
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|atan2|0.0
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|cbrt|0.0 or 1.0
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|cos|0.0
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|cosh|0.0
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|exp|0.0 or 1.0
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|expm1|0.0
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|log|0.0 or 1.0
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|log10|0.0 or 1.0
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|sin|0.0
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|sinh|0.0
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|sqrt|0.0 or 1.0
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|tan|0.0
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|tanh|0.0
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|toDegrees|0.0 or 1.0
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|toRadians|0.0
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|===
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== How to fix it
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Ask yourself if the questionable operation represents the desired calculation or if a value used is erroneous.
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If the calculation is correct, replace it with the result to avoid having to perform the unnecessary operation at runtime.
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=== Code examples
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==== Noncompliant code example
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[source,java,diff-id=1,diff-type=noncompliant]
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----
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public void doMath(int a) {
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double res1 = Math.floor((double)a); // Noncompliant, the result will always be equal to '(double) a'
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double res2 = Math.ceil(4.2); // Noncompliant, the result will always be 5.0
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double res3 = Math.atan(0.0); // Noncompliant, the result will always be 0.0
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}
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----
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==== Compliant solution
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[source,java,diff-id=1,diff-type=compliant]
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----
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public void doMath(int a) {
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double res1 = a; // Compliant
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double res2 = 5.0; // Compliant
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double res3 = 0.0; // Compliant
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}
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Remove this unnecessary call to "Math.xxx".
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endif::env-github,rspecator-view[]
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