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Code Analyzer for Java

There is a newer version: 8.6.0.37351

Why is this an issue?
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.
Noncompliant code example
float a = 16777216.0f;
float b = 1.0f;
float c = a + b; // Noncompliant; yields 1.6777216E7 not 1.6777217E7

double d = a + b; // Noncompliant; addition is still between 2 floats

Compliant solution
float a = 16777216.0f;
float b = 1.0f;
BigDecimal c = BigDecimal.valueOf(a).add(BigDecimal.valueOf(b));

double d = (double)a + (double)b;

Exceptions
This rule doesn’t raise an issue when the mathematical expression is only used to build a string.
System.out.println("["+getName()+"] " +
           "\n\tMax time to retrieve connection:"+(max/1000f/1000f)+" ms.");

Resources

   CERT, FLP02-C. - Avoid using floating-point numbers when precise computation is
  needed