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我正在尝试实现多对多关系。在将数据从数据库获取到实体时工作正常，但在尝试将新值插入连接表时失败。我有三个表：job、job_prozedur 和 prozedur。连接表包含父表（job 和 prozedur）的外键和一些额外的列。

实体类是：

@Entity
@Table(name = "DOK_JOB")
Public class Job implements Serializable {

private static final long serialVersionUID = 1L;

private Integer id;
private String name;    

private List<JobProzedur> jobProzedurList = new ArrayList<JobProzedur>();

public Job() {}

@Id
@SequenceGenerator(name="seqJob", sequenceName="DOK_SEQ_1", allocationSize=1)
@GeneratedValue(generator="seqJob")
@Column(name = "JOB_ID")
public Integer getId() {
    return id;
}

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

@Column(name = "JOB_NAME")
public String getName() {
    return name;
}

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

@OneToMany(fetch = FetchType.EAGER, mappedBy = "job", cascade = CascadeType.ALL, orphanRemoval=true)
@OrderBy(value = "sortLnr")
@Cascade({org.hibernate.annotations.CascadeType.ALL})
public List<JobProzedur> getJobProzedurList() {
    return jobProzedurList;
}

public void setJobProzedurList(List<JobProzedur> jobProzedurList) {
    this.jobProzedurList = jobProzedurList;
}

@Override
public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((id == null) ? 0 : id.hashCode());
    return result;
}

@Override
public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;
    Job other = (Job) obj;
    if (id == null) {
        if (other.id != null)
            return false;
    } else if (!id.equals(other.id))
        return false;
    return true;
}
}

-

@Entity
@Table(name = "DOK_JOB_PROZEDUR")
public class JobProzedur implements Serializable {

private static final long serialVersionUID = 7971463524201735449L;

private JobProzedurId id = new JobProzedurId();
private Integer sortLnr;

private Job job;
private Prozedur proz;

public JobProzedur() {}

@EmbeddedId
public JobProzedurId getId() {
    return id;
}

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

@Column(name = "SORT_LNR")
public Integer getSortLnr() {
    return sortLnr;
}

public void setSortLnr(Integer sortLnr) {
    this.sortLnr = sortLnr;
}   

@ManyToOne(fetch=FetchType.EAGER)
@JoinColumn(name = "JOB_ID", referencedColumnName = "JOB_ID", insertable=false, updatable=false, nullable=false)
public Job getJob() {
    return job;
}

public void setJob(Job job) {
    this.job = job;
}

@ManyToOne(fetch=FetchType.EAGER)
@JoinColumn(name = "PROZ_ID", referencedColumnName = "PROZ_ID", insertable=false, updatable=false)
public Prozedur getProz() {
    return proz;
}

public void setProz(Prozedur proz) {
    this.proz = proz;
}

@Override
public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((id == null) ? 0 : id.hashCode());
    return result;
}

@Override
public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;
    JobProzedur other = (JobProzedur) obj;
    if (id == null) {
        if (other.id != null)
            return false;
    } else if (!id.equals(other.id))
        return false;
    return true;
}

}

-

@Embeddable
public class JobProzedurId implements Serializable {

private static final long serialVersionUID = 1L;    

private Integer jobId;
private Integer prozId; 

public JobProzedurId() {}   

public JobProzedurId(Integer jobId, Integer prozId) {
    super();
    this.jobId = jobId;
    this.prozId = prozId;
}

@Column(name = "JOB_ID", nullable=false)
public Integer getJobId() {
    return jobId;
}

public void setJobId(Integer jobId) {
    this.jobId = jobId;
}

@Column(name = "PROZ_ID")
public Integer getProzId() {
    return prozId;
}

public void setProzId(Integer prozId) {
    this.prozId = prozId;
}

@Override
public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((jobId == null) ? 0 : jobId.hashCode());
    result = prime * result + ((prozId == null) ? 0 : prozId.hashCode());
    return result;
}

@Override
public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;
    JobProzedurId other = (JobProzedurId) obj;
    if (jobId == null) {
        if (other.jobId != null)
            return false;
    } else if (!jobId.equals(other.jobId))
        return false;
    if (prozId == null) {
        if (other.prozId != null)
            return false;
    } else if (!prozId.equals(other.prozId))
        return false;
    return true;
}

@Override
public String toString() {
    return "JobProzedurId [jobId=" + jobId + ", prozId=" + prozId + "]";
}

}

-

@Entity
@Table(name = "DOK_PROZEDUR")
public class Prozedur implements Serializable {

private static final long serialVersionUID = 1L;

private Integer id;
private String dbName;
private String schemaName;
private String packageName;
private String name;

public Prozedur() {}

@Id
@SequenceGenerator(name="seqProz", sequenceName="DOK_SEQ_1", allocationSize=1)
@GeneratedValue(generator="seqProz")
@Column(name = "PROZ_ID")
public Integer getId() {
    return id;
}

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

@Column(name = "DB_NAME")
public String getDbName() {
    return dbName;
}

public void setDbName(String dbName) {
    this.dbName = dbName;
}

@Column(name = "SCHEMA_NAME")
public String getSchemaName() {
    return schemaName;
}

public void setSchemaName(String schemaName) {
    this.schemaName = schemaName;
}

@Column(name = "PACKAGE_NAME")
public String getPackageName() {
    return packageName;
}

public void setPackageName(String packageName) {
    this.packageName = packageName;
}

@Column(name = "PROZ_NAME")
public String getName() {
    return name;
}

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

@Override
public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((id == null) ? 0 : id.hashCode());
    return result;
}

@Override
public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;
    Prozedur other = (Prozedur) obj;
    if (id == null) {
        if (other.id != null)
            return false;
    } else if (!id.equals(other.id))
        return false;
    return true;
}

}

我将 prozedur 分配给工作并持久化的代码部分是：

//      ...
//      ...
    JobProzedur jobProz = new JobProzedur();
    jobProz.setJob(job);
    jobProz.setProz(proz);

    job.getJobProzedurList().add(jobProz);

    entityManager.persist(job);
    entityManager.flush();

坚持时我得到异常：

org.hibernate.exception.ConstraintViolationException: ORA-01400: cannot insert NULL into ("DOK"."DOK_JOB_PROZEDUR"."JOB_ID")

我不知道为什么hibernate在持久化期间不为连接表中的外键列赋值。更新有效，因为我手动分配了这些值，但这不是正确的方法。任何帮助表示赞赏。我已经为此工作了几天，但我没有看到任何解决方案。请帮忙！

4

1 回答 1

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您忘记在和上添加@MapsId注释JobProzedur.getProz()JobProzedut.getJob()

编辑：正如@PepperBob 所说：不应将关联标记为可插入=false 和可更新=false，因为您正是想插入它们。

但是，通过使用单列、自动生成的主键而不是复合主键，我会让我的生活更轻松，应用程序更快。使用唯一约束来保证不能存在具有相同作业 ID 和相同 prozedur ID 的两行。

于 2013-05-20T08:39:29.907 回答