java - Jackson deserialization with unknown dynamic properties

Question

I have a JSON string like:

"shipping_profiles": {
  "563": {
    "name": "name",
    "value": "value"            
  },
  "564": {
    "name": "name",
    "value": "value"            
  },
  "565": {
    "name": "name",
    "value": "value"            
  },
  "566": {
    "name": "name",
    "value": "value"            
  }
}

Now I am parsing it with Jackson 2.0. I am trying to get a List<shipping_profiles> from the JSON string.

Is it possible?

Answer 1

Your shipping_profiles property doesn't look like array. It represent object with dynamic properties, so we should treat it like an object. If we do not know anything about properties we can use @JsonAnySetter annotation. Algorithm could looks like below:

1. Deserialize JSON into JSON-model classes.
2. Convert dynamic objects (maps) into app's POJO classes using ObjectMapper
3. Use app's POJO whenever you want.

Please see my example implementation. I hope, it help you solve your problem. Input JSON:

{
   "shipping_profiles":{
      "563":{
         "name":"name563",
         "value":"value563"
      },
      "564":{
         "name":"name564",
         "value":"value564"
      },
      "565":{
         "name":"name565",
         "value":"value565"
      },
      "566":{
         "name":"name566",
         "value":"value566"
      }
   }
}

Example program:

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonProgram {

    public static void main(String[] args) throws IOException {
        ObjectMapper mapper = new ObjectMapper();

        File source = new File("X:/test.json");
        Entity entity = mapper.readValue(source, Entity.class);
        ShippingProfiles shippingProfiles = entity.getShippingProfiles();
        List<Map<String, String>> profileMaps = shippingProfiles.getProfiles();

        List<Profile> profiles = new ArrayList<Profile>(profileMaps.size());
        for (Map<String, String> item : profileMaps) {
            profiles.add(mapper.convertValue(item, Profile.class));
        }
        System.out.println(profiles);
    }
}

class Entity {

    @JsonProperty("shipping_profiles")
    private ShippingProfiles shippingProfiles;

    public ShippingProfiles getShippingProfiles() {
        return shippingProfiles;
    }

    public void setShippingProfiles(ShippingProfiles shippingProfiles) {
        this.shippingProfiles = shippingProfiles;
    }
}

class ShippingProfiles {

    private List<Map<String, String>> profiles = new ArrayList<Map<String, String>>();

    @JsonAnySetter
    public void setDynamicProperty(String name, Map<String, String> map) {
        profiles.add(map);
    }

    public List<Map<String, String>> getProfiles() {
        return profiles;
    }

    public void setProfiles(List<Map<String, String>> profiles) {
        this.profiles = profiles;
    }
}

class Profile {

    private String name;
    private String value;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }

    @Override
    public String toString() {
        return "Profile [name=" + name + ", value=" + value + "]";
    }
}

Above app prints:

[Profile [name=name563, value=value563], Profile [name=name564, value=value564], Profile [name=name565, value=value565], Profile [name=name566, value=value566]]