Make deserialization work for lists of non-static inner classes about jackson-core HOT 6 CLOSED

To test, I used:

import static org.junit.Assert.assertEquals;

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

import org.junit.Before;
import org.junit.Test;

import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonTest {

  @Before
  public void setUp() throws Exception {}

  @Test
  public void test() throws IOException {

    Dog dog = new Dog();
    dog.name = "Spike";
    dog.legs = new ArrayList<Dog.Leg>();
    dog.legs.add(dog.new Leg());
    dog.legs.add(dog.new Leg());
    dog.legs.get(0).length = 5;
    dog.legs.get(1).length = 4;

    ObjectMapper mapper = new ObjectMapper();

    String dogJson = mapper.writeValueAsString(dog);
    System.out.println(dogJson);
    // output: {"name":"Spike","legs":[{length: 5}, {length: 4}]}

    // currently throws JsonMappingException
    Dog dogCopy = mapper.readValue(dogJson, Dog.class);
    assertEquals(dogCopy.legs.get(1).length, 4);
    // prefer fully populated Dog instance
  }

  public static class Dog
  {
    public String name;
    public List<Leg> legs;

    public class Leg {
      public int length;
    }
  }
}

from jackson-core.

So to be clear, this doesn't work with properties that are collections (Lists) of inner classes, nor for 'normal' properties in conjunction with Inclusion.NON_DEFAULT (the latter should possibly be a separate bug?).

from jackson-core.

Right, it has to be non-static inner class of "parent" class. Otherwise "implicit 'this'" is not known.

I have not tried this with Collections (like Lists) or Maps; it may just be omission due to differing JsonDeserializer implementations.

If you want to edit the title to reflect this, it should be possible to fix this. Although whether it can be done for 1.9.x is an open question (while it can be viewed as a bug, amount of refactoring work may mean it's impractical for 1.x).

from jackson-core.

(OK, it's midnight and I'm useless at coming up with plausible examples, but I've updated them anyway. I'm sorry Spike now has only 2 legs and they're different sizes, it was the best I could come up with...)

from jackson-core.

Hehe. Perfect. Oh. I need to move this to 'jackson-databind' (silly github without ability to share Issue trackers...).

Oh, also, this is good -- I assumed incorrectly that this was for non-static List type. Would have tried totally different test case.

from jackson-core.

Not sure if this can be supported actually. If there are still hopes for supporting this, please re-create for "jackson-databind" project, since that is where support would be added. This tracker is for streaming parser/generator.

from jackson-core.