private static boolean isConstantContent(PsiVariable array) {
    Boolean isConstantArray = CachedValuesManager.<Boolean>getCachedValue(array, () -> CachedValueProvider.Result
      .create(!ContainerUtil.exists(VariableAccessUtils.getVariableReferences(array), 
                                    ExpressionUtils::canBeMutated), 
              PsiModificationTracker.MODIFICATION_COUNT));
    return Boolean.TRUE.equals(isConstantArray);
  }
private static boolean isConstantContent(PsiVariable array)