Conditional naming of POJO classes

Question

Our problem is, our service GET /services/v1/myobject returns object named Xyz. This representation is used by multiple existing clients.

The new service GET /services/v2/myobject needs to expose exact same object but with different name, say XyzLmn

Now one obvious solution would be to create two classes Xyz and XyzLmn, then copy Xyz into XyzLmn and expose XyzLmn in the v2.

What I am looking for is, how can I keep the same java pojo class Xyz and conditionally serialize it to either XyzLmn or Xyz ?

score 0 · Answer 1 · answered Feb 25 '17 at 23:47

0

have you try to add the @JsonIgnoreProperties(ignoreUnknown = true) on your domain object?

answered Feb 25 '17 at 23:47

Mary Zheng

1
2

I am not the consumer of 'GET /services/v1/myobject` I am producer of it. – Ajeet Ganga Feb 26 '17 at 03:33
have you try using Java Generic type? such as @JsonIgnoreProperties(ignoreUnknown = true) @JsonSerialize(include = JsonSerialize.Inclusion.NON_NULL) public class MyEntity { private String version; private T VersionedEntity; } – Mary Zheng Feb 27 '17 at 02:00

score 0 · Accepted Answer · answered Feb 26 '17 at 04:28

One solution is:

Write a customer serializer that emits XyzLmn

Register the customer serializer conditionally

public class XyzWrapperSerializer extends StdSerializer<Item> {

public ItemSerializer() {
    this(null);
}

public ItemSerializer(Class<Item> t) {
    super(t);
}

@Override
public void serialize(
  Item value, JsonGenerator jgen, SerializerProvider provider) 
  throws IOException, JsonProcessingException {

    jgen.writeStartObject();
    jgen.writeNumberField("XyzLmn", value.id);
    jgen.writeEndObject();
} }

XyzWrapper myItem = new XyzWrapper(1, "theItem", new User(2, "theUser"));
ObjectMapper mapper = new ObjectMapper();

SimpleModule module = new SimpleModule();
module.addSerializer(XyzWrapper.class, new XyzWrapperSerializer());
mapper.registerModule(module);

String serialized = mapper.writeValueAsString(myItem);

Conditional naming of POJO classes

2 Answers2