无法序列化类org.springframework.data.mongodb.core.geo.GeoJsonPoint

Question

我正在使用MongoDB Near查找最近的点，getMills是基于LatLng查找最近的点的方法。在获取数据和映射之前，它运行良好。映射时返回以下错误。 我的问题是我如何将类序列化为GeoJsonPoint？

返回此错误：无法序列化org.springframework.data.mongodb.core.geo.GeoJsonPoint类。

private List<Mill> getMills(GetNearByMillsRequest getNearByMillsRequest, BasicResponse basicResponse) {
        // get farmerPosition
        LatLng fieldPosition = getNearByMillsRequest.getFieldPosition();

        double Longitude = fieldPosition.getLongitude();
        double Latitude = fieldPosition.getLatitude();

        System.out.println("Longitude : " + Longitude  + "Latitude : "+ Latitude);

        // creating GeoJson Object for farmer field location...
        Point point = new Point(Latitude,Longitude);
        GeoJsonPoint farmerFieldPosition = new GeoJsonPoint(point);

        Float distance = getNearByMillsRequest.getDistance();

        // find crop by crop Name
        Query query = new Query();
        query.addCriteria(Criteria.where(Mill.Constants.MILL_CROP_REQUIRED).elemMatch(Criteria.where(MillCropRequired.Constants.CROP).is(getNearByMillsRequest.getCrop())));        
        query.addCriteria(Criteria.where(Mill.Constants.MILL_LOCATION).near(farmerFieldPosition));

        // TODO Get radius from UserPreferences
        NearQuery nearQuery = NearQuery.near(farmerFieldPosition).maxDistance(new Distance(distance, Metrics.KILOMETERS));
        nearQuery.query(query);
        nearQuery.spherical(true);  // if using 2dsphere index, otherwise delete or set false
        nearQuery.num(10);

        // Problem occurs here, in mapping part...
        GeoResults<Mill> results = millDAO.getMongoOperations().geoNear(nearQuery, Mill.class);

        System.out.println("results : " + results.getContent().size());

        if (results.getContent().isEmpty()) {
            basicResponse.setErrorCode(ErrorCode.FORBIDDEN_ERROR);
            basicResponse.setResponse("No Crop Found for this region.");
            return null;
        }

        List<GeoResult<Mill>> geoResults = results.getContent();

        //   add nearBy Mills and return this list...
        List<Mill> nearByMills = new ArrayList<>();

        for (GeoResult<Mill> result : geoResults) {
            Mill mill = result.getContent();
            nearByMills.add(mill);
        }

        return nearByMills;
    }

这是我的工厂实体。

public class Mill extends AbstractEntity {

    private String vendorId;
    private String name;
    private String emailAddress;
    private String countryCode;
    private String phoneNumber;
    private String postalAddress;

    @GeoSpatialIndexed(type = GeoSpatialIndexType.GEO_2DSPHERE)
    private GeoJsonPoint millLocation;

    private String ginningCapacity;
    private String storageCapacity;
    private ArrayList<MillCropRequired> millCropRequired;

    public String getVendorId() {
        return vendorId;
    }

    public void setVendorId(String vendorId) {
        this.vendorId = vendorId;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getEmailAddress() {
        return emailAddress;
    }

    public void setEmailAddress(String emailAddress) {
        this.emailAddress = emailAddress;
    }

    public String getCountryCode() {
        return countryCode;
    }

    public void setCountryCode(String countryCode) {
        this.countryCode = countryCode;
    }

    public String getPhoneNumber() {
        return phoneNumber;
    }

    public void setPhoneNumber(String phoneNumber) {
        this.phoneNumber = phoneNumber;
    }

    public String getPostalAddress() {
        return postalAddress;
    }

    public void setPostalAddress(String postalAddress) {
        this.postalAddress = postalAddress;
    }


    public GeoJsonPoint getMillLocation() {
        return millLocation;
    }

    public void setMillLocation(GeoJsonPoint millLocation) {
        this.millLocation = millLocation;
    }

    public String getGinningCapacity() {
        return ginningCapacity;
    }

    public void setGinningCapacity(String ginningCapacity) {
        this.ginningCapacity = ginningCapacity;
    }

    public ArrayList<MillCropRequired> getCropRequirnment() {
        return millCropRequired;
    }

    public void setCropRequirnment(ArrayList<MillCropRequired> millCropRequired) {
        this.millCropRequired = millCropRequired;
    }

    public String getStorageCapacity() {
        return storageCapacity;
    }

    public void setStorageCapacity(String storageCapacity) {
        this.storageCapacity = storageCapacity;
    }

    public static class Constants extends AbstractEntity.Constants {
        public static final String PHONE_NUMBER = "phoneNumber";
        public static final String VENDOR_ID = "vendorId";
        public static final String MILL_CROP_REQUIRED = "millCropRequired";
        public static final String MILL_LOCATION = "millLocation";
    }
}