docs: @Override
      protected void _acceptTimestampVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint)
          throws JsonMappingException
      {
          SerializerProvider prov = visitor.getProvider();
          if ((prov != null) && useNanoseconds(prov)) {
              JsonNumberFormatVisitor v2 = visitor.expectNumberFormat(typeHint);
              if (v2 != null) {
                  v2.numberType(NumberType.BIG_DECIMAL);
              }
          } else {
              JsonIntegerFormatVisitor v2 = visitor.expectIntegerFormat(typeHint);
              if (v2 != null) {
                  v2.numberType(NumberType.LONG);
              }
          }
      }