40 lines
1007 B
Plaintext
40 lines
1007 B
Plaintext
For small numbers, ``++float++`` math has enough precision to yield the expected value, but for larger numbers, it does not. ``++BigDecimal++`` is the best alternative, but if a primitive is required, use a ``++double++``.
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== Noncompliant Code Example
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----
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float a = 16777216.0f;
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float b = 1.0f;
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float c = a + b; // Noncompliant; yields 1.6777216E7 not 1.6777217E7
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double d = a + b; // Noncompliant; addition is still between 2 floats
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----
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== Compliant Solution
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----
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float a = 16777216.0f;
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float b = 1.0f;
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BigDecimal c = BigDecimal.valueOf(a).add(BigDecimal.valueOf(b));
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double d = (double)a + (double)b;
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----
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== Exceptions
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This rule doesn't raise an issue when the mathematical expression is only used to build a string.
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----
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System.out.println("["+getName()+"] " +
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"\n\tMax time to retrieve connection:"+(max/1000f/1000f)+" ms.");
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----
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== See
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* https://wiki.sei.cmu.edu/confluence/x/CtcxBQ[CERT, FLP02-C.] - Avoid using floating-point numbers when precise computation is needed
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