Different names of JSON property during serialization and deserialization

kiRach picture kiRach · Dec 19, 2011 · Viewed 205.3k times · Source

Is it possible: to have one field in class, but different names for it during serialization/deserialization in Jackson library?

For example, I have class "Coordiantes".

class Coordinates{
  int red;
}

For deserialization from JSON want to have format like this:

{
  "red":12
}

But when I will serialize object, result should be like this one:

{
  "r":12
}

I tried to implement this by applying @JsonProperty annotation both on getter and setter (with different values):

class Coordiantes{
    int red;

    @JsonProperty("r")
    public byte getRed() {
      return red;
    }

    @JsonProperty("red")
    public void setRed(byte red) {
      this.red = red;
    }
}

but I got an exception:

org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "red"

Answer

bezmax picture bezmax · Dec 19, 2011

Just tested and this works:

public class Coordinates {
    byte red;

    @JsonProperty("r")
    public byte getR() {
      return red;
    }

    @JsonProperty("red")
    public void setRed(byte red) {
      this.red = red;
    }
}

The idea is that method names should be different, so jackson parses it as different fields, not as one field.

Here is test code:

Coordinates c = new Coordinates();
c.setRed((byte) 5);

ObjectMapper mapper = new ObjectMapper();
System.out.println("Serialization: " + mapper.writeValueAsString(c));

Coordinates r = mapper.readValue("{\"red\":25}",Coordinates.class);
System.out.println("Deserialization: " + r.getR());

Result:

Serialization: {"r":5}
Deserialization: 25