如何在 SpringBoot 中返回列表

Question

code below return me list of two objects like this:

[
    {
        value: "ssss",
    },
    {
        value: "ssss",
    },
]

but i want to return list like this:

{
    value1:"xxxx",
    value2:"xxxx"
}

here is my code

    @Override
    public List<OrderModel> getOrderByCode(UserEntity user) throws ErrorException {

        List<UserEntity> userOrder = userRepository.findByUserAndOrderCodeIn(user, Arrays.asList(OrderCodes.OK, OrderCodes.DONE));

        List<OrderModel> om = new ArrayList<OrderModel>();
        for(UserAnswerEntity userAnswerEntity : userAnswers){
            OrderModel orderModel = new OrderModel();
            orderModel.setValue(userAnswerEntity.getValue());

            om.add(orderModel );
        }

        return om;
    }

public class OrderModel{

    String value;

//get,set
}

can someon tell me how can i return only list like above?

Answer 1

You are trying to make a custom response. One of the possible way is this

Map<String,String> map = new HashMap<String,String>();
map.put("key1", "value1");
map.put("key2", "value2");

System.out.println(map.toString().replace("{", "[").replace("}", "]"));

Answer 2

Change the return type of getOrderByCode() to string and convert your List object to JSON string.

private static final ObjectMapper jsonMapper = new ObjectMapper().setSerializationInclusion(Include.NON_NULL);
return jsonMapper.writeValueAsString(om);

Answer 3

for you example, you can use Map instead of List

try this:

  AtomicInteger index = new AtomicInteger()
  Function<UserAnswerEntity, String> createIndex = (userAnswer) -> "value" + index.getAndIncrement();
  return userAnswers.stream().collect(Collectors.toMap(createIndex, UserAnswerEntity::getValue));