Java Jackson映射缺少映射POJO类的一个键值

我面临一个问题。Jackson映射缺少映射POJO类的一个键值

使用这个maven依赖性-

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.6.3</version>
</dependency>

波乔班

 public class AllGroupResponse {
        private String status;
        private String data;
        private String message;
        private String tag;
        private List<GroupTable> groupListDTO;
    }
public class GroupTable {

    private String id;
    private String groupId;
    private String groupName;
    private String address;
    private String groupLimit;
    private String groupPairingCode;
    private String zoneId;
    private String siteContactNumber;
    private String programId;
    private String projectId;
    private String createdBy;
    private String updatedBy;
    private String partyProfileId;
    private String groupType;
    private Date createdDate;
    private Date updatedDate;
    private Date groupPairingValidity;
    private String groupManagerName;
    private String groupManagerEmail;
    private List<String> userEmailIds;
    private String description;
    private String status;
    private String city;
    private String state;

    private String parentReference;
}

映射到POJO类之后。打印到字符串-

AllGroupResponse{status='SUCCESS', data='null', message='Get all the group list for user.', tag='GROUP_LIST_FOUND', groupListDTO=[GroupTable{id='0cab0526-ce7c-4cd8-80cd-77e1e7e52b29', groupId='demo site_39329fbf-97ce-4474-bfab-db0f00ffa4b9', groupName='Demo Site', address='Mu', groupLimit='null', groupPairingCode='null', zoneId='demotest-zone_13f74715-fad9-4517-9cbd-bd47fa7c4df7', siteContactNumber='', programId='null', projectId='ab4dafed-7fd9-46c0-ab9a-b28d756c4f11', createdBy='null', updatedBy='nishant@gmail.com', partyProfileId='null', groupType='PARENT', createdDate=Fri May 10 17:45:42 IST 2019, updatedDate=Fri Jul 05 12:40:47 IST 2019, groupPairingValidity=null, groupManagerName='null', groupManagerEmail='null', userEmailIds=[jl@gmail.com], description='null', status='UPDATED', city='null', state='null'}]} 

在这里我发现键

“parentReference”：“null”

丢失。我知道null值是字符串格式的。但它应该映射为字符串

---

我不明白为什么会这样。没有发生任何异常。请告诉我解决方案。

忘记在toString（）方法中添加更新的参数- 谢谢@alexey28

@Override
    public String toString() {
        return "GroupTable{" +
                "id='" + id + '\'' +
                ", groupId='" + groupId + '\'' +
                ", groupName='" + groupName + '\'' +
                ", address='" + address + '\'' +
                ", groupLimit='" + groupLimit + '\'' +
                ", groupPairingCode='" + groupPairingCode + '\'' +
                ", zoneId='" + zoneId + '\'' +
                ", siteContactNumber='" + siteContactNumber + '\'' +
                ", programId='" + programId + '\'' +
                ", projectId='" + projectId + '\'' +
                ", createdBy='" + createdBy + '\'' +
                ", updatedBy='" + updatedBy + '\'' +
                ", partyProfileId='" + partyProfileId + '\'' +
                ", groupType='" + groupType + '\'' +
                ", createdDate=" + createdDate +
                ", updatedDate=" + updatedDate +
                ", groupPairingValidity=" + groupPairingValidity +
                ", groupManagerName='" + groupManagerName + '\'' +
                ", groupManagerEmail='" + groupManagerEmail + '\'' +
                ", userEmailIds=" + userEmailIds +
                ", description='" + description + '\'' +
                ", status='" + status + '\'' +
                ", city='" + city + '\'' +
                ", state='" + state + '\'' +
                ", parentReference='" + parentReference + '\'' +
                '}';
    }

---

可以添加POJO类的代码吗？该字段可能丢失。请检查我是否已更新POJO类。字段在那里，它没有丢失@Arnaud ClaudelThe POJO似乎不是正确的，您试图映射的是

AllGroupResponse

对象，而不是

GroupTable

对象。

private String parentReference

位于类的末尾，您后来添加了它吗？您确定正在运行最新的编译版本吗？我认为这是toString（）问题。您是否尝试在allGroupResponse的调试和查看字段中停止？还要检查toString实现

AllGroupResponse{status='SUCCESS', data='null', message='Get all the group list for user.', tag='GROUP_LIST_FOUND', groupListDTO=[GroupTable{id='0cab0526-ce7c-4cd8-80cd-77e1e7e52b29', groupId='demo site_39329fbf-97ce-4474-bfab-db0f00ffa4b9', groupName='Demo Site', address='Mu', groupLimit='null', groupPairingCode='null', zoneId='demotest-zone_13f74715-fad9-4517-9cbd-bd47fa7c4df7', siteContactNumber='', programId='null', projectId='ab4dafed-7fd9-46c0-ab9a-b28d756c4f11', createdBy='null', updatedBy='nishant@gmail.com', partyProfileId='null', groupType='PARENT', createdDate=Fri May 10 17:45:42 IST 2019, updatedDate=Fri Jul 05 12:40:47 IST 2019, groupPairingValidity=null, groupManagerName='null', groupManagerEmail='null', userEmailIds=[jl@gmail.com], description='null', status='UPDATED', city='null', state='null'}]} 

@Override
    public String toString() {
        return "GroupTable{" +
                "id='" + id + '\'' +
                ", groupId='" + groupId + '\'' +
                ", groupName='" + groupName + '\'' +
                ", address='" + address + '\'' +
                ", groupLimit='" + groupLimit + '\'' +
                ", groupPairingCode='" + groupPairingCode + '\'' +
                ", zoneId='" + zoneId + '\'' +
                ", siteContactNumber='" + siteContactNumber + '\'' +
                ", programId='" + programId + '\'' +
                ", projectId='" + projectId + '\'' +
                ", createdBy='" + createdBy + '\'' +
                ", updatedBy='" + updatedBy + '\'' +
                ", partyProfileId='" + partyProfileId + '\'' +
                ", groupType='" + groupType + '\'' +
                ", createdDate=" + createdDate +
                ", updatedDate=" + updatedDate +
                ", groupPairingValidity=" + groupPairingValidity +
                ", groupManagerName='" + groupManagerName + '\'' +
                ", groupManagerEmail='" + groupManagerEmail + '\'' +
                ", userEmailIds=" + userEmailIds +
                ", description='" + description + '\'' +
                ", status='" + status + '\'' +
                ", city='" + city + '\'' +
                ", state='" + state + '\'' +
                ", parentReference='" + parentReference + '\'' +
                '}';
    }