我有个奇怪的问题，在网上什么也没找到。
以前有人看到过这个错误吗？
原因：org.hibernate.mappingexception:无法确定列的类型：java.util.list，位于表：root:[org.hibernate.mapping.column（frequency）]
以前没人写过这句话的频率是多少。
这是我的课：

package com.hotels.river.ratehawkModels;

import java.util.List;

import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Root {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long rootId;

    private String address;

    @ElementCollection
    private List<AmenityGroup> amenity_groups;

    private String check_in_time;

    private String check_out_time;

    @ElementCollection
    private List<DescriptionStruct> description_struct;

    private String id;

    private List<String> images;

    private String kind;

    private double latitude;

    private double longitude;

    private String name;

    private String phone;

    @ElementCollection
    private List<PolicyStruct> policy_struct;

    private String postal_code;

    @ElementCollection
    private List<RoomGroup> room_groups;

    private Region region;

    private int star_rating;

    private String email;

    private int semantic_version;

    @ElementCollection
    private List<String> serp_filters;

    private boolean is_closed;

    private MetapolicyStruct metapolicy_struct;

    private String metapolicy_extra_info;

    private String star_certificate;

    private Facts facts;

    @ElementCollection
    private List<String> payment_methods;

    private String hotel_chain;

    public Root() {
        super();
        // TODO Auto-generated constructor stub
    }
    public Root(String address, List<AmenityGroup> amenity_groups, String check_in_time, String check_out_time,
            List<DescriptionStruct> description_struct, String id, List<String> images, String kind, double latitude,
            double longitude, String name, String phone, List<PolicyStruct> policy_struct, String postal_code,
            List<RoomGroup> room_groups, Region region, int star_rating, String email, int semantic_version,
            List<String> serp_filters, boolean is_closed, MetapolicyStruct metapolicy_struct,
            String metapolicy_extra_info, String star_certificate, Facts facts, List<String> payment_methods,
            String hotel_chain) {
        super();
        this.address = address;
        this.amenity_groups = amenity_groups;
        this.check_in_time = check_in_time;
        this.check_out_time = check_out_time;
        this.description_struct = description_struct;
        this.id = id;
        this.images = images;
        this.kind = kind;
        this.latitude = latitude;
        this.longitude = longitude;
        this.name = name;
        this.phone = phone;
        this.policy_struct = policy_struct;
        this.postal_code = postal_code;
        this.room_groups = room_groups;
        this.region = region;
        this.star_rating = star_rating;
        this.email = email;
        this.semantic_version = semantic_version;
        this.serp_filters = serp_filters;
        this.is_closed = is_closed;
        this.metapolicy_struct = metapolicy_struct;
        this.metapolicy_extra_info = metapolicy_extra_info;
        this.star_certificate = star_certificate;
        this.facts = facts;
        this.payment_methods = payment_methods;
        this.hotel_chain = hotel_chain;
    }
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
    public List<AmenityGroup> getAmenity_groups() {
        return amenity_groups;
    }
    public void setAmenity_groups(List<AmenityGroup> amenity_groups) {
        this.amenity_groups = amenity_groups;
    }
    public String getCheck_in_time() {
        return check_in_time;
    }
    public void setCheck_in_time(String check_in_time) {
        this.check_in_time = check_in_time;
    }
    public String getCheck_out_time() {
        return check_out_time;
    }
    public void setCheck_out_time(String check_out_time) {
        this.check_out_time = check_out_time;
    }
    public List<DescriptionStruct> getDescription_struct() {
        return description_struct;
    }
    public void setDescription_struct(List<DescriptionStruct> description_struct) {
        this.description_struct = description_struct;
    }
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public List<String> getImages() {
        return images;
    }
    public void setImages(List<String> images) {
        this.images = images;
    }
    public String getKind() {
        return kind;
    }
    public void setKind(String kind) {
        this.kind = kind;
    }
    public double getLatitude() {
        return latitude;
    }
    public void setLatitude(double latitude) {
        this.latitude = latitude;
    }
    public double getLongitude() {
        return longitude;
    }
    public void setLongitude(double longitude) {
        this.longitude = longitude;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
    public List<PolicyStruct> getPolicy_struct() {
        return policy_struct;
    }
    public void setPolicy_struct(List<PolicyStruct> policy_struct) {
        this.policy_struct = policy_struct;
    }
    public String getPostal_code() {
        return postal_code;
    }
    public void setPostal_code(String postal_code) {
        this.postal_code = postal_code;
    }
    public List<RoomGroup> getRoom_groups() {
        return room_groups;
    }
    public void setRoom_groups(List<RoomGroup> room_groups) {
        this.room_groups = room_groups;
    }
    public Region getRegion() {
        return region;
    }
    public void setRegion(Region region) {
        this.region = region;
    }
    public int getStar_rating() {
        return star_rating;
    }
    public void setStar_rating(int star_rating) {
        this.star_rating = star_rating;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public int getSemantic_version() {
        return semantic_version;
    }
    public void setSemantic_version(int semantic_version) {
        this.semantic_version = semantic_version;
    }
    public List<String> getSerp_filters() {
        return serp_filters;
    }
    public void setSerp_filters(List<String> serp_filters) {
        this.serp_filters = serp_filters;
    }
    public boolean isIs_closed() {
        return is_closed;
    }
    public void setIs_closed(boolean is_closed) {
        this.is_closed = is_closed;
    }
    public MetapolicyStruct getMetapolicy_struct() {
        return metapolicy_struct;
    }
    public void setMetapolicy_struct(MetapolicyStruct metapolicy_struct) {
        this.metapolicy_struct = metapolicy_struct;
    }
    public String getMetapolicy_extra_info() {
        return metapolicy_extra_info;
    }
    public void setMetapolicy_extra_info(String metapolicy_extra_info) {
        this.metapolicy_extra_info = metapolicy_extra_info;
    }
    public String getStar_certificate() {
        return star_certificate;
    }
    public void setStar_certificate(String star_certificate) {
        this.star_certificate = star_certificate;
    }
    public Facts getFacts() {
        return facts;
    }
    public void setFacts(Facts facts) {
        this.facts = facts;
    }
    public List<String> getPayment_methods() {
        return payment_methods;
    }
    public void setPayment_methods(List<String> payment_methods) {
        this.payment_methods = payment_methods;
    }
    public String getHotel_chain() {
        return hotel_chain;
    }
    public void setHotel_chain(String hotel_chain) {
        this.hotel_chain = hotel_chain;
    }
    @Override
    public String toString() {
        return "Root [address=" + address + ", amenity_groups=" + amenity_groups + ", check_in_time=" + check_in_time
                + ", check_out_time=" + check_out_time + ", description_struct=" + description_struct + ", id=" + id
                + ", images=" + images + ", kind=" + kind + ", latitude=" + latitude + ", longitude=" + longitude
                + ", name=" + name + ", phone=" + phone + ", policy_struct=" + policy_struct + ", postal_code="
                + postal_code + ", room_groups=" + room_groups + ", region=" + region + ", star_rating=" + star_rating
                + ", email=" + email + ", semantic_version=" + semantic_version + ", serp_filters=" + serp_filters
                + ", is_closed=" + is_closed + ", metapolicy_struct=" + metapolicy_struct + ", metapolicy_extra_info="
                + metapolicy_extra_info + ", star_certificate=" + star_certificate + ", facts=" + facts
                + ", payment_methods=" + payment_methods + ", hotel_chain=" + hotel_chain + "]";
    }

}

这是我的实体，其中有6个可嵌入类。拜托，有人知道吗？？