Question

我正在尝试本地化我的jpa应用程序。要做到这一点，我在我的类中使用@MapKeyColumn属性。所以我用这种方式定义了这个类：

@Entity
@Inheritance(strategy = InheritanceType.JOINED)
@Table(name = "BIENTOO_SPORT")
public class Sport implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "sportId")
    private Long id;

    @Column(name = "code")
    private String code;

    @OneToMany(fetch = FetchType.LAZY, orphanRemoval = true, mappedBy = "sport")
    @MapKeyColumn(name = "SPORT_LANGUAGE_KEY")
    private Map<String,SportLocalizedString> sportLocalizedString;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public Map<String, SportLocalizedString> getSportLocalizedString() {
        return sportLocalizedString;
    }

    public void setSportLocalizedString(Map<String, SportLocalizedString> sportLocalizedString) {
        this.sportLocalizedString = sportLocalizedString;
    }

    public SportLocalizedString newSportLocalizedString(){
        return new SportLocalizedString();
    }

    @Entity
    @Table(name = "BIENTOO_SPORT_LOCALIZED_STRING")
    public class SportLocalizedString implements Serializable {

        @Id
        @GeneratedValue(generator = "bientooSportLocalizedString", strategy = GenerationType.TABLE)
        @TableGenerator(name = "bientooSportLocalizedString", table = "SEQUENCE_GENERATOR", pkColumnName = "ID_NAME", valueColumnName = "ID_VAL", pkColumnValue = "sportLocalizedString", allocationSize = 50)
        @Column(name = "SPORT_LOCALIZED_ID")
        private Long id;

        @Column(name = "SPORT_LANGUAGE_KEY")
        private String language;

        @Column(name = "SPORT_LANGUAGE_NAME")
        private String name;

        @ManyToOne
        private Sport sport;

        public String getName() {
            return name;
        }

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

        public String getLanguage() {
            return language;
        }

        public void setLanguage(String language) {
            this.language = language;
        }

        public Sport getSport() {
            return sport;
        }

        public void setSport(Sport sport) {
            this.sport = sport;
        }
    }

}

正如您在Sport中所看到的，我与内部类有一个OneToMany关系。当我启动应用程序时，一切正常。但是当我检索Sport对象时，Map sportLocalizedString为null。我做错了什么？

Answer 1

尝试将@MapKeyColumn(name = "SPORT_LANGUAGE_KEY")替换为@MapKey(name = "language")

JPA - 即使数据在数据库中，MapKeyColumn也为null

1 个答案: