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double area(double radius) {
  return 4.0 * Math.PI * radius * radius;
}

double volume(double radius) {
  return 4.0/3.0 * Math.PI * radius * radius * radius;
}

double greatCircleCircumference(double radius) {
  return 2 * Math.PI * radius;
}

Noncompliant Code Example

This noncompliant code example defines a constant BUFSIZE, but then defeats the purpose of defining BUFSIZE as a constant by assuming a specific value for BUFSIZE in the following expression:

private final int BUFSIZE = 512;
// ...
nblocks = 1 + ((nbytes - 1) >> 9); /* BUFSIZE = 512 = 2^9 */

The programmer has assumed that it is obvious that BUFSIZE is 512, and right-shifting 9 bits is the same (for positive numbers) as dividing by 512. However, if BUFSIZE changes to 1024 in the future, modifications will be both difficult and error prone.

Compliant Solution

This compliant solution uses the identifier assigned to the constant value in the expression.

nblocks = 1 + (nbytes - 1) / BUFSIZE;

Exceptions

DCL02-EX1: The use of symbolic constants should be restricted to cases where they improve the readability and maintainability of the code. When the intent of the literal is obvious, or where the literal is not likely to change, use of symbolic constants can impair code readability. The following noncompliant code example obscures the meaning of the code by using too many symbolic constants.

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