@JsonDeserialize(using = CustomDeserializer.class)
public class Plan {
 private String ex;
 private String alpha;
}
@JsonComponent
public class CustomDeserializer extends JsonDeserializer<Plan> {
  @Override
    public Plan deserialize(JsonParser jsonParser, DeserializationContext deserializationContext)
      throws IOException, JsonProcessingException {
        //TODO WRITE LOGIC TO DECODE J
        TreeNode treeNode = jsonParser.getCodec().readTree(jsonParser);
        TextNode ex = (TextNode) treeNode.get("ex");
    }
}