Java 在JPA中使用继承时的复合外键问题

我有一个JPA实体StatEntity，它有一个复合主键，它也是另一个实体花名册的外键。使用@JoinColumns（{@JoinColumn…}）注释将其设置为@OneToOne关系

StatEntity扩展另一个实体CoreStatEntity，该实体被设置为@MappedSuperClass，其中as RosterEntity使用单表继承策略扩展另一个实体CoreRoster

@Entity
@Table(name = "Stats")
@IdClass(value = StatsEntity.Key.class)
public class StatsEntity extends CoreStatsEntity implements
    Stats {

@Id
private Integer competitionId;

@Id
private Integer playerId;

@Id
private Integer teamId;

@OneToOne
@JoinColumns({
        @JoinColumn(name = "competitionId", referencedColumnName = "competitionId", insertable = false, updatable=false),
        @JoinColumn(name = "playerId", referencedColumnName = "personId", insertable = false, updatable=false),
        @JoinColumn(name = "teamId", referencedColumnName = "teamId", insertable = false, updatable=false) })
private RosterEntity roster;


....

}

statentity.Key

 @Embeddable
public static class Key implements Serializable {

    private static final long serialVersionUID = -7349082038890396790L;

    @Column(name = "competitionId", insertable = false, updatable = false)
    private Integer competitionId;

    @Column(name = "playerId", insertable = false, updatable = false)
    private Integer playerId;

    @Column(name = "teamId", insertable = false, updatable = false)
    private Integer teamId;

    public Key() {
        super();
    }

    public Key(int competitionId, int playerId, int teamId) {
        this.competitionId = Integer.valueOf(competitionId);
        this.playerId = Integer.valueOf(playerId);
        this.teamId = Integer.valueOf(teamId);
    }

    public int getTeamId() {
        return teamId.intValue();
    }

    public void setTeamId(int teamId) {
        this.teamId = Integer.valueOf(teamId);
    }

    public int getPlayerId() {
        return playerId.intValue();
    }

    public void setPlayerId(int playerId) {
        this.playerId = Integer.valueOf(playerId);
    }

    public int getCompetitionId() {
        return competitionId.intValue();
    }

    public void setCompetitionId(int CompetitionId) {
        this.competitionId = Integer.valueOf(CompetitionId);
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#equals(java.lang.Object)
     */
    @Override
    public boolean equals(Object object) {
        if (object == this) {
            return true;
        }
        if (!(object instanceof Key)) {
            return false;
        }

        Key other = (Key) object;
        return Utils.equals(other.getTeamId(), this.getTeamId())
                && Utils.equals(other.getPlayerId(), this.getPlayerId())
                && Utils.equals(other.getCompetitionId(),
                        this.getCompetitionId());
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode() {
        return Utils.hashCode(this.teamId, this.playerId,
                this.competitionId);

    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return Utils.toString("CompetitionPlayerStatsEntity.Key",
                this.teamId, this.playerId, this.competitionId);
    }
}

 @Entity
 @DiscriminatorValue("20")
  public class RosterEntity extends
    CoreRosterEntity  {

    //.... attributes, getters, setters

    }

corestantentity.java

@MappedSuperclass
public abstract class CoreStatsEntity
{}

@Entity
@DiscriminatorValue("0")
@Table(name="Roster")
@IdClass(CoreRoster.Key.class)           

@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="discriminator", discriminatorType=DiscriminatorType.INTEGER)
public class CoreRosterEntity  {

        private static final long serialVersionUID = 1521639115446682871L;

@Id
private Integer competitionId;

@Id
private Integer teamId;

@Id
private Integer playerId;

//.. getters, setters and other attributes

@Embeddable
public static class Key implements Serializable {

    private static final long serialVersionUID = 2L;

    @Column(name="competitionId", nullable=false)
    private Integer competitionId;

    @Column(name="teamId", nullable=false)
    private Integer teamId;

    @Column(name="personId", nullable=false)
    private Integer playerId;

    public Key() {
        super();
    }

    public Key(int competitionId, int teamId, int playerId) {
        this.competitionId = Integer.valueOf(competitionId);
        this.teamId = Integer.valueOf(teamId);
        this.playerId = Integer.valueOf(playerId);
    }

    public int getPlayerId() {
        return playerId.intValue();
    }

    public void setPlayerId(int playerId) {
        this.playerId = Integer.valueOf(playerId);
    }

    public int getTeamId() {
        return teamId.intValue();
    }

    public void setTeamId(int teamId) {
        this.teamId = Integer.valueOf(teamId);
    }

    public int getCompetitionId() {
        return this.competitionId.intValue();
    }

    public void setCompetitionId(int competitionId) {
        this.competitionId = Integer.valueOf(competitionId);
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#equals(java.lang.Object)
     */
    @Override
    public boolean equals(Object object) {
        if (object == this) { return true; }
        if (!(object instanceof Key)) { return false; }

        Key other = (Key) object;
        return Utils.equals(other.getCompetitionId(), this.getCompetitionId()) &&
               Utils.equals(other.getTeamId(), this.getTeamId()) &&
               Utils.equals(other.getPlayerId(), this.getPlayerId());
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode() {
        return Utils.hashCode(this.competitionId, this.teamId,
                              this.playerId);
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return Utils.toString("CoreRoster.Key",
                              this.competitionId, this.teamId,
                              this.playerId);
    }
}

讲台性

 @Embeddable
public static class Key implements Serializable {

    private static final long serialVersionUID = -7349082038890396790L;

    @Column(name = "competitionId", insertable = false, updatable = false)
    private Integer competitionId;

    @Column(name = "playerId", insertable = false, updatable = false)
    private Integer playerId;

    @Column(name = "teamId", insertable = false, updatable = false)
    private Integer teamId;

    public Key() {
        super();
    }

    public Key(int competitionId, int playerId, int teamId) {
        this.competitionId = Integer.valueOf(competitionId);
        this.playerId = Integer.valueOf(playerId);
        this.teamId = Integer.valueOf(teamId);
    }

    public int getTeamId() {
        return teamId.intValue();
    }

    public void setTeamId(int teamId) {
        this.teamId = Integer.valueOf(teamId);
    }

    public int getPlayerId() {
        return playerId.intValue();
    }

    public void setPlayerId(int playerId) {
        this.playerId = Integer.valueOf(playerId);
    }

    public int getCompetitionId() {
        return competitionId.intValue();
    }

    public void setCompetitionId(int CompetitionId) {
        this.competitionId = Integer.valueOf(CompetitionId);
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#equals(java.lang.Object)
     */
    @Override
    public boolean equals(Object object) {
        if (object == this) {
            return true;
        }
        if (!(object instanceof Key)) {
            return false;
        }

        Key other = (Key) object;
        return Utils.equals(other.getTeamId(), this.getTeamId())
                && Utils.equals(other.getPlayerId(), this.getPlayerId())
                && Utils.equals(other.getCompetitionId(),
                        this.getCompetitionId());
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode() {
        return Utils.hashCode(this.teamId, this.playerId,
                this.competitionId);

    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return Utils.toString("CompetitionPlayerStatsEntity.Key",
                this.teamId, this.playerId, this.competitionId);
    }
}

 @Entity
 @DiscriminatorValue("20")
  public class RosterEntity extends
    CoreRosterEntity  {

    //.... attributes, getters, setters

    }

coresterentity.java

@MappedSuperclass
public abstract class CoreStatsEntity
{}

@Entity
@DiscriminatorValue("0")
@Table(name="Roster")
@IdClass(CoreRoster.Key.class)           

@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="discriminator", discriminatorType=DiscriminatorType.INTEGER)
public class CoreRosterEntity  {

        private static final long serialVersionUID = 1521639115446682871L;

@Id
private Integer competitionId;

@Id
private Integer teamId;

@Id
private Integer playerId;

//.. getters, setters and other attributes

@Embeddable
public static class Key implements Serializable {

    private static final long serialVersionUID = 2L;

    @Column(name="competitionId", nullable=false)
    private Integer competitionId;

    @Column(name="teamId", nullable=false)
    private Integer teamId;

    @Column(name="personId", nullable=false)
    private Integer playerId;

    public Key() {
        super();
    }

    public Key(int competitionId, int teamId, int playerId) {
        this.competitionId = Integer.valueOf(competitionId);
        this.teamId = Integer.valueOf(teamId);
        this.playerId = Integer.valueOf(playerId);
    }

    public int getPlayerId() {
        return playerId.intValue();
    }

    public void setPlayerId(int playerId) {
        this.playerId = Integer.valueOf(playerId);
    }

    public int getTeamId() {
        return teamId.intValue();
    }

    public void setTeamId(int teamId) {
        this.teamId = Integer.valueOf(teamId);
    }

    public int getCompetitionId() {
        return this.competitionId.intValue();
    }

    public void setCompetitionId(int competitionId) {
        this.competitionId = Integer.valueOf(competitionId);
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#equals(java.lang.Object)
     */
    @Override
    public boolean equals(Object object) {
        if (object == this) { return true; }
        if (!(object instanceof Key)) { return false; }

        Key other = (Key) object;
        return Utils.equals(other.getCompetitionId(), this.getCompetitionId()) &&
               Utils.equals(other.getTeamId(), this.getTeamId()) &&
               Utils.equals(other.getPlayerId(), this.getPlayerId());
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode() {
        return Utils.hashCode(this.competitionId, this.teamId,
                              this.playerId);
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return Utils.toString("CoreRoster.Key",
                              this.competitionId, this.teamId,
                              this.playerId);
    }
}

}

coretroster.java中的coretroster.Key.class

@MappedSuperclass
public abstract class CoreStatsEntity
{}

@Entity
@DiscriminatorValue("0")
@Table(name="Roster")
@IdClass(CoreRoster.Key.class)           

@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="discriminator", discriminatorType=DiscriminatorType.INTEGER)
public class CoreRosterEntity  {

        private static final long serialVersionUID = 1521639115446682871L;

@Id
private Integer competitionId;

@Id
private Integer teamId;

@Id
private Integer playerId;

//.. getters, setters and other attributes

@Embeddable
public static class Key implements Serializable {

    private static final long serialVersionUID = 2L;

    @Column(name="competitionId", nullable=false)
    private Integer competitionId;

    @Column(name="teamId", nullable=false)
    private Integer teamId;

    @Column(name="personId", nullable=false)
    private Integer playerId;

    public Key() {
        super();
    }

    public Key(int competitionId, int teamId, int playerId) {
        this.competitionId = Integer.valueOf(competitionId);
        this.teamId = Integer.valueOf(teamId);
        this.playerId = Integer.valueOf(playerId);
    }

    public int getPlayerId() {
        return playerId.intValue();
    }

    public void setPlayerId(int playerId) {
        this.playerId = Integer.valueOf(playerId);
    }

    public int getTeamId() {
        return teamId.intValue();
    }

    public void setTeamId(int teamId) {
        this.teamId = Integer.valueOf(teamId);
    }

    public int getCompetitionId() {
        return this.competitionId.intValue();
    }

    public void setCompetitionId(int competitionId) {
        this.competitionId = Integer.valueOf(competitionId);
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#equals(java.lang.Object)
     */
    @Override
    public boolean equals(Object object) {
        if (object == this) { return true; }
        if (!(object instanceof Key)) { return false; }

        Key other = (Key) object;
        return Utils.equals(other.getCompetitionId(), this.getCompetitionId()) &&
               Utils.equals(other.getTeamId(), this.getTeamId()) &&
               Utils.equals(other.getPlayerId(), this.getPlayerId());
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode() {
        return Utils.hashCode(this.competitionId, this.teamId,
                              this.playerId);
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return Utils.toString("CoreRoster.Key",
                              this.competitionId, this.teamId,
                              this.playerId);
    }
}

当我持久化statentity时，它就会持久化。但当我尝试使用主键查找它时，它会给我一个错误：

    StatsEntity playerStats = new StatsEntity();
    //set all values
this.persist(playerStats);              
entityManager.find(StatsEntity.class, playerStats.getId()); //getId returns the composite primary key

 java.lang.IllegalArgumentException: Provided id of the wrong type for class   com.sports.RosterEntity. Expected: class com.sports.CoreRoster$Key, got class com.espn.sports.StatsEntity$Key

我的第一个问题是，我给出的@OneToOne映射是否正确？

---

如果它是正确的，那么当我尝试使用primarykey查找实体时，为什么会出现此错误。

您尚未发布完整的源代码，尤其是主键类的源代码，但您已将外键映射为只读，这是单列多次映射时所必需的

但是，我看到您的id列与RosterEntity的外键3列完全相同，对吗？在这种情况下，这个排他性应该是您的ID，这将简化您的设计

---

getId（）方法的返回类型是什么？问题可能与IdClass的定义或用法有关

编辑了该问题。getId的返回类型是Object，但我返回的对象是statEntity.Key。让我试试你的建议花名册。键不能作为ID，因为其中的列是不同的名称。（personId而不是playerId）对DB列添加了一个小更改（感谢DBA），现在我已将键作为花名册。工作。谢谢