Deserializing a Java Object that extends an ArrayList with Jackson

Question

I have the following Class that I can serialize in a way that I want.

@JsonSerialize(using = MySerializer.class)
@JsonDeserialize(using = MyDeserialize.class)
public class TryToSerialize extends ArrayList<String>
{
    private int number;
    private String word;
    public TryToSerialize(){}
    public TryToSerialize(int number, String word){
        this.number = number;
        this.word = word;
    }

    @JsonProperty
    public int getNumber() {
        return number;
    }

    public void setNumber(int number) {
        this.number = number;
    }
    @JsonProperty
    public String getWord() {
        return word;
    }

    public void setWord(String word) {
        this.word = word;
    }
}

It has been serialized with the following serializer

class MySerializer extends JsonSerializer<TryToSerialize> 
{
    @Override
    public void serialize(TryToSerialize toSerialize, JsonGenerator jgen, SerializerProvider provider) throws IOException, JsonProcessingException 
    {
       jgen.writeStartObject();
        jgen.writeNumberField("number", toSerialize.getNumber());
        jgen.writeStringField("word", toSerialize.getWord());
        provider.defaultSerializeField("values", toSerialize.iterator(), jgen);
        jgen.writeEndObject();
    }
}

This code will serialize the object into the following:

{"number":10,"word":"Working","values":["first","second","third"]}

Now I am trying to deserialize it, but I am unsure of how to handle the processing of the ArrayList portion. So far I have something like this:

class MyDeserialize extends JsonDeserializer<TryToSerialize> {
    @Override
    public TryToSerialize deserialize(JsonParser jp, DeserializationContext ctxt) 
      throws IOException, JsonProcessingException {
        JsonNode node = jp.getCodec().readTree(jp);

        int number = (Integer) ((IntNode) node.get("number")).numberValue();
        String word = node.get("word").asText();


        return new TryToSerialize(number, word);
    }
}

Any help would be greatly appreciated.

Answer 1

An option with what you have so far is, since you have the JsonNode available and you know that you have serialized the list into the property values , to iterate over the values property and add the contents to your class.

class MyDeserializer extends JsonDeserializer<TryToSerialize> {
    @Override
    public TryToSerialize deserialize(JsonParser jp, DeserializationContext ctxt)
            throws IOException, JsonProcessingException {
        JsonNode node = jp.getCodec().readTree(jp);

        int number = (Integer) ((IntNode) node.get("number")).getNumberValue();
        String word = node.get("word").asText();

        TryToSerialize deserialized = new TryToSerialize(number, word);
        JsonNode valuesNode = node.get("values");
        if (valuesNode.isArray()) {
            Iterator<JsonNode> arrayIterator = ((ArrayNode) valuesNode).getElements();
            while (arrayIterator.hasNext()) {
                deserialized.add(arrayIterator.next().getTextValue());
            }

        }

        return deserialized;
    }
}