我有一个Java方法，它使用流方法创建JSON格式的客户信息，并在使用SmallRye Mutiny中的Multi以异步方法创建时返回。
我想给这个JSON添加一个 Package 器，这个JSON是用Jackson JsonGenerator创建的，我不知道怎么添加，我相信我需要用Multi.createBy().concatenating()来实现这个。
下面是我的方法：

public static Multi<Customer> generateCustomer(final Input input) {
    try {
        return Multi.createFrom().publisher(new CustomerPublisher(input));
    } catch (Exception e) {
        throw new NewException("Exception occurred during the generation of Customer : " + e);
    }
}

上面的方法当前异步返回如下内容：

[
  {
    "name":"Batman",
    "age":45,
    "city":"gotham"
  },
  {
    "name":"superman",
    "age":50,
    "city":"moon"
  }
]

我想给这个JSON添加一个 Package 器，并创建如下所示的内容：

{
  "isA": "customerDocument",
  "createdOn": "2022-10-10T12:29:43",
  "customerBody": {
    "customerList": [
      {
        "name": "Batman",
        "age": 45,
        "city": "gotham"
      },
      {
        "name": "superman",
        "age": 50,
        "city": "moon"
      }
    ]
  }
}

因此，我添加了一个执行此操作的方法，并且我希望调用相同的方法，但是我无法将相同的方法附加到我的return Multi.createFrom().publisher

public class CustomerGenerator {

    private ByteArrayOutputStream jsonOutput;
    private JsonGenerator jsonGenerator;

    private CustomerGenerator() {
        try {
            jsonOutput = new ByteArrayOutputStream();
            jsonGenerator = new JsonFactory().createGenerator(jsonOutput).useDefaultPrettyPrinter();
        } catch (IOException ex) {
            throw new TestDataGeneratorException("Exception occurred during the generation of customer document : " + ex);
        }
    }

    public static Multi < Customer > generateCustomer(final Input input) {
        CustomerGenerator customerGenerator = new CustomerGenerator();
        customerGenerator.wrapperStart();
        try {
            return Multi.createFrom().publisher(new CustomerPublisher(input));
        } catch (Exception e) {
            throw new NewException("Exception occurred during the generation of Customer : " + e);
        } finally {
            System.out.println("ALL DONE");
            customerGenerator.wrapperEnd();
        }
    }

    public void wrapperStart() {
        try {
            jsonGenerator.writeStartObject();
            jsonGenerator.writeStringField("type", "customerDocument");
            jsonGenerator.writeStringField("creationDate", Instant.now().toString());
            jsonGenerator.writeFieldName("customerBody");
            jsonGenerator.writeStartObject();
            jsonGenerator.writeFieldName("customerList");
        } catch (IOException ex) {
            throw new TestDataGeneratorException("Exception occurred during customer document wrapper creation : " + ex);
        }
    }

    public void wrapperEnd() {
        try {
            jsonGenerator.writeEndObject(); // End body
            jsonGenerator.writeEndObject(); // End whole json file
        } catch (IOException ex) {
            throw new TestDataGeneratorException("Exception occurred during customer document wrapper creation : " + ex);
        } finally {
            try {
                jsonGenerator.close();
                System.out.println("JSON DOCUMENT STRING : " + jsonOutput.toString());
            } catch (Exception e) {
                // do nothing
            }
        }
    }

}