Unable to deserialize list directly inside rootelement using Jackson XML

Question

I am unable to deserialize a list that is directory a child of the root element, I have tried various kinds of things.

My code:

private static class Cards {
    @JacksonXmlElementWrapper(localName = "Cards")
    private List<Card> cards;

    public List<Card> getCards() {
        return new ArrayList<>(cards);
    }
}

private static class Card {
    @JsonProperty("Name")
    private String name;

    @JsonProperty("Image")
    private String image;

    @JsonProperty("CardType")
    private String cardType;

    private final Map<String, Integer> resources = new HashMap<>();

    private boolean duplicateResources = false;
    private final List<String> duplicateResourceNames = new ArrayList<>();

    @JsonAnySetter
    private void addResource(final String name, final Object value) {
        if (resources.containsKey(name)) {
            duplicateResources = true;
            duplicateResourceNames.add(name);
        }
        resources.put(name, Integer.parseInt(value.toString()));
    }

    public String getName() {
        return name;
    }

    public String getImage() {
        return image;
    }

    public String getCardType() {
        return cardType;
    }

    @JsonAnyGetter
    public Map<String, Integer> getResources() {
        if (duplicateResources) {
            throw new UncheckedCardLoadingException("Resources " + duplicateResourceNames + " have duplicate entries");
        }
        return new HashMap<>(resources);
    }
}

And:

ObjectMapper xmlMapper = new XmlMapper();
Cards cards = xmlMapper.readValue(path.toFile(), Cards.class);

When trying to deserialize the following XML:

<Cards>
    <Card>
        <Name>test</Name>
        <Image></Image>
        <CardType>test</CardType>
    </Card>
</Cards>

It gives as error:

com.cardshifter.core.cardloader.CardLoadingException: com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "Card" (class com.cardshifter.core.cardloader.XmlCardLoader$Cards), not marked as ignorable (one known property: "Cards"]) at [Source: C:\Users\Frank\Dropbox\NetbeansProjects\Cardshifter\cardshifter-core\target\test-classes\com\cardshifter\core\cardloader\single-card.xml; line: 3, column: 9] (through reference chain: com.cardshifter.core.cardloader.Cards["Card"])

Answer 1

First of all, look at these:

@JacksonXmlElementWrapper(localName = "Cards")
private List<Card> cards;

And then look at the error:

com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "Card" (class com.cardshifter.core.cardloader.XmlCardLoader$Cards)

Nowhere does it say "Card" in your class.

Secondly, after fixing that, here's how I solved your entire loading:

private static class Cards {
    @JacksonXmlElementWrapper(localName = "Card")
    @JsonProperty("Card")
    private List<Card> card = new ArrayList<>();

    @JsonSetter
    public void setCard(Card card) {
        this.card.add(card);
    }
}

The setCard method simply tells Jackson that if it encounters this, it should interpret it as a Card, and then you provide the method that adds it to the array.