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.");
