I'm facing problem with Jackson's ObjectMapper using JAXB annotations. To be concrete, I'm having collection with interface generic information and although I can deserialize input from XML, it is not possible with Jackson (using JAXB introspector). Maybe I'm just missing some configuration property or JAXB annotation? The problem is that "abstract types can only be instantiated with additional type information", I thought @XmlElementRef (or @XmlElement) with type information will handle this problem, but obviosly it does not.

Please note, that I want to stay only with JAXB annotations if possible.
E.g. using @JsonTypeInfo or @JsonDeserialize would be the last thing to do.

IEntry.java:

```
@XmlSeeAlso(Entry.class)
public interface IEntry {
    String getValue();
}

```

Entry.java:

```
@XmlRootElement(name = "entry")
public class Entry implements IEntry {

    @XmlElement(name = "value")
    String value;

    public Entry() {
    }

    public Entry(String value) {
        this.value = value;
    }

    public String getValue() {
        return value;
    }
}

```

Aggregator.java:

```
@XmlRootElement(name = "aggregator")
public class Aggregator {

    @XmlElementRef(type = Entry.class)
    private Set<IEntry> entries;

    public Aggregator() {
    }

    public Aggregator(Set<IEntry> entries) {
        this.entries = entries;
    }

    public Set<IEntry> getEntries() {
        return entries;
    }
}

```

Test method:

```
@Test
    public void testSerialization() throws Exception {
        ObjectMapper om = new ObjectMapper();
        AnnotationIntrospector intr = new JaxbAnnotationIntrospector();
        om.getDeserializationConfig().withAnnotationIntrospector(intr);

        String json = "{\"entries\":[{\"value\":\"X\"},{\"value\":\"Y\"},{\"value\":\"Z\"}]}\";\n}";
        Aggregator agr = om.readValue(json, Aggregator.class);
    }

```

Thanks for all response