Why is this an issue?

This rule involves the use of Math.abs and negation on numbers that could be MIN_VALUE. It is a problem because it can lead to incorrect results and unexpected behavior in the program.

When Math.abs and negation are used on numbers that could be MIN_VALUE, the result can be incorrect due to integer overflow. Common methods that can return a MIN_VALUE and raise an issue when used together with Math.abs are:

• Random.nextInt() and Random.nextLong()
• hashCode()
• compareTo()

Alternatively, the absExact() method throws an ArithmeticException for MIN_VALUE.

Noncompliant code example

public void doSomething(String str) {
  if (Math.abs(str.hashCode()) > 0) { // Noncompliant
    // ...
  }
}

Compliant solution

public void doSomething(String str) {
  if (str.hashCode() != 0) {
    // ...
  }
}

Resources

• Oracle SDK 20 - Math.abs(int)