public final @InspectionMessage String getMethodCompatibilityProblem(PsiMethod method) {
    return validators().map(fn -> fn.apply(method)).filter(Objects::nonNull).findFirst()
                       .map((JavaAnalysisBundle.message("contract.return.value.validation.prefix", this)+' ')::concat)
                       .orElse(null);
  }
public final @InspectionMessage String getMethodCompatibilityProblem(PsiMethod method)