Jackson : map nested object

Question

Using jackson, i wonder if it's possible du map json to Java with nested Object that are not like the json structure.

Here an exemple of what i want to do.

Json :

{
  a = "someValue",
  b = "someValue",
  c = "someValue"
}

Java :

public class AnObject {
  @JsonProperty("a")
  private String value;

  //Nested object
  private SomeObject;
}

public class SomeObject {
  @JsonProperty("b")
  private String value1;

  @JsonProperry("c")
  private String value2;
}

Is it possible ?

Answer 1

Use the JsonUnwrapped annotation:

@JsonUnwrapped
private final SomeObject someObject;

which unwrappes all of SomeObject's fields into the parent, resulting in the following when serializing:

{"a":"foo","b":"bar","c":"baz"}

Answer 2

Using ObjectMapper you can convert JSON string to Object. Use JsonUnwrapped in your AnObject class over someObject field.

@JsonUnwrapped
private SomeObject someObject;

then read JSON string and convert it to AnObject.

ObjectMapper mapper = new ObjectMapper();
try {
   AnObject anObject1 = mapper.readValue(jsonString, AnObject.class);   
} catch (IOException e) {
    e.printStackTrace();
}