Why is this an issue?

When a type variable or a wildcard declares an upper bound that is final, the parametrization is not generic at all because it accepts one and only one type at runtime: the one that is final. Instead of using Generics, it’s simpler to directly use the concrete final class.

Noncompliant code example

public static <T extends String> T getMyString() { // Noncompliant; String is a "final" class and so can't be extended
 [...]
}

Compliant solution

public static String getMyString() { // Compliant
  [...]
}