Is there a way using Jackson JSON Processor to do custom field level serialization? For example, I'd like to have the class
public class Person {
public String name;
public int age;
public int favoriteNumber;
}
serialized to the follow JSON:
{ "name": "Joe", "age": 25, "favoriteNumber": "123" }
Note that age=25 is encoded as a number while favoriteNumber=123 is encoded as a string. Out of the box Jackson marshalls int
to a number. In this case I want favoriteNumber to be encoded as a string.
You can implement a custom serializer as follows:
public class Person {
public String name;
public int age;
@JsonSerialize(using = IntToStringSerializer.class, as=String.class)
public int favoriteNumber:
}
public class IntToStringSerializer extends JsonSerializer<Integer> {
@Override
public void serialize(Integer tmpInt,
JsonGenerator jsonGenerator,
SerializerProvider serializerProvider)
throws IOException, JsonProcessingException {
jsonGenerator.writeObject(tmpInt.toString());
}
}
Java should handle the autoboxing from int
to Integer
for you.