问题
Attached is my json. I am receiving this from an endpoint. I have the object type in my consuming app. the object contains; success, message and loggedInMember (which is an object). In the json, the feeClasses contains a lot of fields and objects etc which is why i have not included the whole json. I am only interested in the success and message fields.
{
"header":{
"messageId":null,
"receivedTimestamp":1611246394839,
"replyTo":null,
"redelivered":false,
"originator":null
},
"internalId":null,
"auditPoints":[
],
"success":true,
"message":"",
"loggedInMember":{
"feeClasses":{
...CONTAINS A LOT OF FIELDS...
}
}
}
I am trying to map this response to the object type, hence essentially leaving loggedInMembers null. This is my test I am trying to run:
public void test() throws JsonProcessingException
{
//String json = "{\"header\":{\"messageId\":null,\"bucketNumber\":null,\"senderSubId\":null,\"senderLocationId\":null,\"onBehalfOfCompId\":null,\"onBehalfOfSubId\":null,\"onBehalfOfLocationId\":null,\"correlationId\":null,\"receivedTimestamp\":1611246394839,\"replyTo\":null,\"redelivered\":false,\"originator\":null},\"internalId\":null,\"auditPoints\":[],\"success\":true,\"message\":\"\",\"loggedInMember\":{\"memberLoginName\":\"BMARTINTEST\",\"memberId\":\"201901241246290000036402D\",\"settlementAccountIds\":[\"201901241246290000036491D\"],\"parentMemberId\":\"1\",\"firmId\":\"990\",\"memberType\":\"INDIVIDUAL\",\"memberAccountType\":\"PROD\",\"password\":\"D1208B304FD7AA6187690A389A5040C1D9B07643\",\"feeClasses\":{\"byId\":{\"201902120947520000559606D\":{\"memberLoginName\":\"BMARTINTEST\",\"feeClassId\":\"201508041827550000942152D\",\"memberFeeClassId\":\"201902120947520000559606D\",\"allocatedDate\":{\"year\":2019,\"month\":2,\"day\":12,\"timeMillis\":1549929600000},\"firstUsedForTradeDate\":{\"year\":2019,\"month\":2,\"day\":12,\"timeMillis\":1549929600000},\"firstUsedForSettlementDate\":null,\"usableFromDate\":{\"year\":2019,\"month\":2,\"day\":12,\"timeMillis\":1549929600000},\"usableToDate\":{\"year\":2019,\"month\":2,\"day\":19,\"timeMillis\":1550534400000},\"usableToTimestamp\":1550613600000,\"usableBusinessDaysAllocated\":6,\"usableBusinessDaysRemaining\":0,\"narrative\":\"Bonus assigned to member at first-time funding of amount 4000.00 : Set expiration date/time\",\"disabled\":false,\"usableForTrade\":true,\"usableForSettlement\":true},\"202001290940390000868824D\":{\"memberLoginName\":\"BMARTINTEST\",\"feeClassId\":\"202001290940340000776406D\",\"memberFeeClassId\":\"202001290940390000868824D\",\"allocatedDate\":{\"year\":2020,\"month\":1,\"day\":29,\"timeMillis\":1580256000000},\"firstUsedForTradeDate\":null,\"firstUsedForSettlementDate\":null,\"usableFromDate\":{\"year\":2020,\"month\":1,\"day\":6,\"timeMillis\":1578268800000},\"usableToDate\":{\"year\":2020,\"month\":2,\"day\":27,\"timeMillis\":1582761600000},\"usableToTimestamp\":1582840800000,\"usableBusinessDaysAllocated\":0,\"usableBusinessDaysRemaining\":0,\"narrative\":\"Added NO_FEES_CLASS\",\"disabled\":false,\"usableForTrade\":true,\"usableForSettlement\":true},\"201901241246290000036417D\":{\"memberLoginName\":\"BMARTINTEST\",\"feeClassId\":\"201508041736360000943781D\",\"memberFeeClassId\":\"201901241246290000036417D\",\"allocatedDate\":{\"year\":2019,\"month\":1,\"day\":24,\"timeMillis\":1548288000000},\"firstUsedForTradeDate\":null,\"firstUsedForSettlementDate\":null,\"usableFromDate\":{\"year\":2019,\"month\":1,\"day\":24,\"timeMillis\":1548288000000},\"usableToDate\":null,\"usableToTimestamp\":null,\"usableBusinessDaysAllocated\":0,\"usableBusinessDaysRemaining\":0,\"narrative\":null,\"disabled\":false,\"usableForTrade\":true,\"usableForSettlement\":true}},\"empty\":false},\"legalName\":\"Martin Birch\",\"taxId\":\"345335454\",\"taxCountryId\":\"US\",\"currency\":\"USD\",\"lastTradeId\":null,\"introducingBrokerMemberId\":null,\"introducingBrokerMemberName\":null,\"introducingBrokerMemberCode\":null,\"clearedByMemberId\":\"SECOND_TEST\",\"clearedByMemberLoginName\":null,\"memberProblems\":[],\"emailNotificationEnabled\":true,\"rtafLevelId\":0,\"rtafAmount\":0,\"maxNumberOfPositionAccounts\":1,\"ciciIdentifier\":null,\"traderRequired\":false,\"interestClass\":\"INDIVIDUAL\",\"memberCreatedDate\":1548333989000,\"parentMemberLoginNames\":[\"NADEX.COM\",\"NADEX\"],\"demoStartDate\":null,\"demoEndDate\":null,\"clientIdMaxLimit\":null,\"memberAccountApplicationFieldData\":null,\"rank\":0,\"uuid\":\"201901241246290000036395D\",\"referrerId\":\"raf4qam5h00s36d\",\"testMember\":false},\"allReplyToSource\":[],\"sendToOriginatorOnly\":false}";
String json = "{\n" +
" \"header\":{\n" +
" \"messageId\":null,\n" +
" \"receivedTimestamp\":1611246394839,\n" +
" \"replyTo\":null,\n" +
" \"redelivered\":false,\n" +
" \"originator\":null\n" +
" },\n" +
" \"internalId\":null,\n" +
" \"auditPoints\":[\n" +
" \n" +
" ],\n" +
" \"success\":true,\n" +
" \"message\":\"\",\n" +
" \"loggedInMember\":{\n" +
" \"feeClasses\":{\n" +
" \n" +
" }\n" +
" }\n" +
"}";
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
objectMapper.addMixIn(LogonResponseMessage.class, LogonResponseMixin.class);
LogonResponseMessage responseMessage = objectMapper.readValue(json, LogonResponseMessage.class);
System.out.println(responseMessage);
}
My mixin:
public abstract class LogonResponseMixin
{
LogonResponseMixin(@JsonProperty("success") boolean success, @JsonProperty("message") String message){};
@JsonIgnore
abstract Member loggedInMember();
@JsonIgnore
abstract MemberFeeClasses feeClasses();
@JsonIgnore
abstract Header header();
}
I am getting the following error: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of domain.xyz.MemberFeeClasses (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
Am i creating the mixin wrong? I have asked in a previous question and using mixin was the general consensus but it doesn't seem to play ball with me.
Thank you.
回答1:
The reason why MemberFeeClasses cannot be constructed is the same as your initial problem, just add a mixin for all classes
See the example below:
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.Getter;
import lombok.Setter;
import java.io.IOException;
public class Test {
//------------------------------------------------//
// PART 1 - MAIN TEST METHOD
//------------------------------------------------//
public static void main(String[] args) throws IOException {
String json = "{\n" +
" \"header\":{" +
" },\n" +
" \"success\":true,\n" +
" \"message\":\"\",\n" +
" \"loggedInMember\":{\n" +
" \"feeClasses\":{\n" +
" \"amount\": \"20\"\n" +
" }\n" +
" }\n" +
"}";
ObjectMapper objectMapper = new ObjectMapper();
//objectMapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
objectMapper.addMixIn(LogonResponseMessage.class, LogonResponseMixin.class);
objectMapper.addMixIn(Member.class, MemberMixin.class);
objectMapper.addMixIn(MemberFee.class, MemberFeeMixin.class);
LogonResponseMessage responseMessage = objectMapper.readValue(json, LogonResponseMessage.class);
System.out.println(responseMessage.loggedInMember.feeClasses.amount);
}
//------------------------------------------------//
// PART 2 - CREATOR MIXIN
//------------------------------------------------//
static abstract class LogonResponseMixin {
LogonResponseMixin(@JsonProperty("success") boolean success,
@JsonProperty("message") String message,
@JsonProperty("header") Header header,
@JsonProperty("loggedInMember") Member member) {
}
}
static abstract class MemberMixin {
MemberMixin(@JsonProperty("feeClasses") MemberFee feeClasses) {
}
}
static abstract class MemberFeeMixin {
@JsonCreator
MemberFeeMixin(@JsonProperty("amount") String amount) {
}
}
//------------------------------------------------//
// PART 3 - EXAMPLE CLASS DEFINITION
//------------------------------------------------//
static class Header {
}
@Getter
@Setter
static class Member {
private MemberFee feeClasses;
public Member(MemberFee feeClasses) {
this.feeClasses = feeClasses;
}
}
@Getter
@Setter
static class MemberFee {
private String amount;
public MemberFee(String amount) {
this.amount = amount;
}
}
@Getter
@Setter
static class LogonResponseMessage {
private boolean success;
private String message;
private Header header;
private Member loggedInMember;
public LogonResponseMessage(boolean success, String message, Header header, Member member) {
this.success = success;
this.message = message;
this.header = header;
this.loggedInMember = member;
}
}
}
来源：https://stackoverflow.com/questions/65834218/unable-to-deserialise-via-mixin