我在使用Jackson反序列化JSON字符串时遇到问题。我收到错误：com.fasterxml.jackson.databind.JsonMappingException：找不到类型[simple type，class RatingDMO]的合适构造函数：无法从JSON对象实例化（需要添加/启用类型信息？）
我将字段映射到JSON文件，并且它的参数可用作属性并且具有相同的类型。
注意： - 如果我提供no-arg构造函数（仅用于检查它是否有效），则测试有效。
我无法在代码中提供/保留默认构造函数，因为模型中的最终字段很少。
mapper.readValue（new File（＆＃34; ratingRequest.json＆＃34;），RatingDMO.class）;
JSON文件： -
{
"company": "Test",
"state": "NJ",
"lob": "PA",
"channel": "IA",
"username": "GlobalBatchUser",
"password": "GlobalBatchUser",
"policyNumber": "Test",
"policyKey": 7267,
"transactionType": "Quote",
"evaluationType": null,
"clientID": null,
"policyTerm": "6",
"effectiveDate": "01/01/1980",
"policyXML": null,
"firstName": null,
"lastName": null,
"businessName": null,
"city": null,
"zip": null,
"effectiveDtStart": "06/06/2013",
"effectiveDtEnd": "06/06/2014",
"searchType": "uw1",
"uuid": null,
"policyStatusCodes": [],
"eAdvisorCoverages": {},
"customCoverages": {},
"defaultCoverages": {},
"action": null,
"type": null,
"selectedCoverage": null,
"motorClubMember": true,
"selectedSubCoveres": null,
"customRated": true,
"policyDMO": {
"policyKey": 0,
"company": "HP",
"state": "NJ",
"lob": "auto",
"channel": null,
"addresses": [
{
"addressId": 0,
"addrLine1Txt": "20 MARTIN RD",
"addrLine2Txt": null,
"addrLine3Txt": null,
"addrLine4Txt": null,
"cityName": "LIVINGSTON",
"cityAliasName": null,
"countyName": null,
"countryCd": null,
"districtCd": null,
"houseNum": null,
"poBoxInd": null,
"stateCd": "NJ",
"zip": "07039",
"zipPlusFour": null,
"addressType": "ADDRESS_RESIDENCE_KEY",
"vehicleId": 0
},
{
"addressId": 0,
"addrLine1Txt": "20 MARTIN RD",
"addrLine2Txt": null,
"addrLine3Txt": null,
"addrLine4Txt": null,
"cityName": "LIVINGSTON",
"cityAliasName": null,
"countyName": null,
"countryCd": null,
"districtCd": null,
"houseNum": null,
"poBoxInd": null,
"stateCd": "NJ",
"zip": "07039",
"zipPlusFour": null,
"addressType": "ADDRESS_MAILING_KEY",
"vehicleId": 0
}
],
"policyInfo": {
"policyKey": 0,
"mailingAddrID": 0,
"priorAddrID": 0,
"residentialAddrId": 0,
"billingAddrId": 0,
"employerAddrId": 0,
"policyNum": "Test",
"policyEffDt": 1371614400000,
"policyExpDt": null,
"companyCD": null,
"stateCD": "NJ",
"term": 0,
"emailId": "KSIRIPURAPU@PLYMOUTHROCK.COM",
"faxNum": null,
"homePhoneNum": null,
"workPhoneNum": null,
"mailingAddrIsSameInd": "Y",
"plfCD": "HIPT",
"affinityCD": null,
"motorClubInd": null,
"homeownerInd": null,
"homeInsCarrierName": null,
"empOrRetEduInstInd": null,
"residenceInsTypeCD": null,
"policyCancelledWithin3YRSIND": null,
"declineEmailInd": null,
"militaryServiceInd": null,
"clueORDInd": null,
"otherInsuranceBasicOrSpecialInd": null,
"healthInsuranceCarrierName": null,
"healthInsurancePolicyNumber": null,
"transactionProgress": "1",
"numOfAccidentInLoanedVehicle": null,
"allInsuredInd": null,
"medicareMediaidInd": null,
"uwCompanyCd": null,
"policyIssueNo": null,
"associatedEduAffilatedOrgInd": null,
"eDocumentsInd": null
},
"eligibility": [],
"policyAgency": {
"policyKey": 0,
"branchID": null,
"agencyID": null,
"producerId": null,
"agencyHierId": 23155,
"agentLoginId": null,
"userName": null,
"userTypeCd": null,
"emailAddressId": null,
"referChannel": "Others"
},
"participants": [
{
"policyKey": 0,
"participantId": 0,
"firstName": "KHAGENDRA",
"middleName": null,
"lastName": "SIRIPURAPU",
"suffix": null,
"birthDate": null,
"ssn": null,
"fid": null,
"gender": "",
"licNum": null,
"licStateCD": null,
"maritalStatusCD": null,
"relationshipToInsCD": "A",
"businessName": null,
"participantRole": "PRIMARY_INSURED"
}
],
"vehicles": [],
"drivers": [
{
"driverId": 0,
"firstName": "KHAGENDRA",
"middleName": null,
"lastName": "SIRIPURAPU",
"licenseAtAge": 0,
"licenseStatusCode": null,
"defenseDriverCourseIndicator": null,
"goodStudentIndicator": null,
"driverTrainingIndicator": null,
"awayAtSchoolIndicator": null,
"incidents": null,
"occupation": null,
"insuredOnOther": null,
"continuousCoverageIndicator": null,
"priorLicenseNumber": null,
"driverCourseDate": null,
"driverCourseName": null,
"firstLicenseNonUSA": null,
"awayAtMilitaryIndicator": null,
"sr22FilingIndicator": null,
"otherPolicyCarrierName": null,
"awayAtSchoolComment": null,
"licenseOosPrior3YrsInd": "N",
"licenseOosPrior3YearsStateCd": null,
"advDriverTrainingDate": null,
"defensiveDriverCourseDate": null,
"otherPolicyTypeCode": null,
"accidentPrvntCourseDate": null,
"phoneNumber": null,
"safetyPledgeInd": null,
"accidents": null,
"violations": null
}
],
"priorCarrier": {
"priorBiLimits": null,
"priorCarrName": null,
"policyKey": 0,
"continuousCoverageDesc": null,
"lapsedReason": null,
"numOfYearOfContinuousCoverage": null,
"activeCurrentPoilcyInd": null
},
"discounts": null,
"companionPolicy": null,
"payment": null
},
"allInsuredInd": "Y",
"medicareMediaidInd": "Y",
"driversGreaterthan65": true
}
POJO班级：
public class RatingDMO implements Serializable {
private static final long serialVersionUID = -433016040176969496L;
private String company;
private String state;
private String lob;
private String channel;
private String username;
private String password;
private String policyNumber;
private long policyKey;
private String transactionType;
private String evaluationType;
private String clientID;
private String policyTerm;
private String effectiveDate;
private String policyXML;
private String webXML;
private String firstName;
private String lastName;
private String businessName;
private String city;
private String zip;
private String effectiveDtStart;
private String effectiveDtEnd;
private String searchType;
private String uuid;
private List<String> policyStatusCodes;
private Map<String,String> eAdvisorCoverages;
private Map<String,String> customCoverages;
private Map<String,String> defaultCoverages;
private String action;
private String type;
private String selectedCoverage;
private boolean motorClubMember;
private String selectedSubCoveres;
private boolean customRated;
private final PolicyDMO policyDMO;
private final String allInsuredInd;
private final String medicareMediaidInd;
private final boolean driversGreaterthan65;
public PolicyRatingRequestDMO(PolicyDMO policyDMO, String allInsuredInd, String medicareMediaidInd, boolean driversGreaterthan65){
this.policyDMO = policyDMO;
this.allInsuredInd = allInsuredInd;
this.medicareMediaidInd = medicareMediaidInd;
this.driversGreaterthan65 = driversGreaterthan65;
}
... }
答案 0 :(得分：8)
默认情况下，Jackson的数据绑定将尝试使用无参数构造函数构造对象，然后从JSON的相应位填充对象的属性。您可以使用注释覆盖此行为
@JsonCreator
public PolicyRatingRequestDMO(@JsonProperty("policyInfo") PolicyDMO policyDMO,
@JsonProperty("allInsuredInd") String allInsuredInd,
@JsonProperty("medicareMediaidInd") String medicareMediaidInd,
@JsonProperty("driversGreaterThan65") boolean driversGreaterthan65){
this.policyDMO = policyDMO;
this.allInsuredInd = allInsuredInd;
this.medicareMediaidInd = medicareMediaidInd;
this.driversGreaterthan65 = driversGreaterthan65;
}
JsonCreator注释告诉Jackson要调用哪个构造函数，并使用JsonProperty注释其参数，以指示JSON中哪些属性对应于构造函数中的哪些参数。 JSON中与构造函数参数不对应的其他属性将通过setter或直接字段访问注入。