@Override
  @Nullable
  protected LocalQuickFix buildFix(Object... infos) {
    final PsiExpression argument = (PsiExpression)infos[0];
    if (!(argument instanceof PsiLiteralExpression)) {
      return null;
    }
    return new NewStringBufferWithCharArgumentFix();
  }
@Override
  @Nullable
  protected LocalQuickFix buildFix(Object... infos)