Jackson handling XML arrays with dynamic fields using the hashmap approach

Question

I have to write a message handler that will process incoming XML messages and pass them on to another module as JSON representations. There are a relatively high of possible messages and I would rather use a single POJO for my purpose. Here is an example XML message.

<Message name="GenericMsg">
    <StartTime>533798131</StartTime> <!-- Unix Timestamp -->

                .
                .
    <!-- Some other fields -->
                .
    <NumberOfItems>2</NumberOfItems>
    <List>
        <ListItem>
            <Speed>100</Speed>
            <Location>
                <lat>38.165748</lat>
                <lon>37.125363</lon>
                <alt>800</alt>
            </Location>
        </ListItem>
        <ListItem>
            <Speed>120</Speed>
            <Location>
                <lat>39.123748</lat>
                <lon>41.312645</lon>
                <alt>850</alt>
            </Location>
        </ListItem>
    </List>
</Message>

And my POJO

public class MsgRepr {
    private Map<String, Object> details = new LinkedHashMap<>();

    public Object get(String key) {
        return this.details.get(key);
    }

    @JsonAnyGetter
    public Map<String, Object> getDetails() {
        return this.details;
    }
    @JsonAnySetter
    public void setDetails(String key, Object value) {
        this.details.put(key,value);
    }
}

This gets converted to the following JSON:

{
  "name" : "GenericMsg",
  "NumberOfItems" : "2",
  "StartTime" : "533798131"
  "List" : {
    "ListItem" :
    [
      {
        "Speed" : "100",
        "Location" : {
          "lat" : "38.165748",
          "lon" : "37.125363",
          "alt" : "800"
        }
      },
      {
        "Speed" : "150",
        "Location" : {
          "lat" : "48.564866",
          "lon" : "35.18795",
          "alt" : "850"
        }
      }
    ]
  }
}

I tried the defaultUseWrapper=false option with no avail. Also, omitting the List/ListItem duality results in only the last element being present.

I know that this can be done by writing a seperate POJO for each message, but I would rather avoid doing that. Is there an alternative XML representation or an alternative approach I can use to correctly convert the json to something similar to the following format?

{
  "name" : "GenericMsg",
  "NumberOfItems" : "2",
  "StartTime" : "533798131"
  "List" :
  [
    {
      "Speed" : "100",
      "Location" : {
        "lat" : "38.165748",
        "lon" : "37.125363",
        "alt" : "800"
      }
    },
    {
      "Speed" : "150",
      "Location" : {
        "lat" : "48.564866",
        "lon" : "35.18795",
        "alt" : "850"
      }
    }
  ]
}

Jackson version 2.13.0

Jackson handling XML arrays with dynamic fields using the hashmap approach

0 Answers0