Hibernate多对多关联删除错误

Question

我有两个类:Employee 和 Award，具有多对多关系。

当尝试删除时，我收到违反约束的错误。我浏览了所有帖子，但没有一个有帮助。

这是代码:

@Entity
@Table(name="TB_AWARD")
public class Award implements Serializable{


    @Id @GeneratedValue
    @Column(name="AWARD_ID")
    private long awardId;

    @ManyToMany(mappedBy="awards")
    @NotFound(action=NotFoundAction.IGNORE)
    private Collection<Employee> employee = new ArrayList<Employee>();

    @Column(name="AWARD_TYPE")
    private String awardType;

    @Column(name="AWARD_DATE")
    private Date awardDate;

    @Column(name="AWARD_DETAILS")
    @Lob
    private String awardDetails;

    @Column(name="REMARK")
    private String remark;

@Entity
@Table(name="TB_EMPLOYEE")
public class Employee implements Serializable {

    @Id @GeneratedValue
    @Column(name="EMPLOYEE_ID")
    private long employeeID;

        @ManyToMany(cascade= CascadeType.ALL)
    private Collection<Award> awards;

Answer 1

您的映射错误，请尝试如下:

@Entity
@Table(name="TB_AWARD")
public class Award implements Serializable{


    @Id @GeneratedValue
    @Column(name="AWARD_ID")
    private long awardId;

    @ManyToMany(targetEntity=Employee.class, cascade = CascadeType.ALL)
    @JoinTable(name = "AWARD_EMPLOYEE", joinColumns = { @JoinColumn(name ="AWARD_ID")},
    inverseJoinColumns = { @JoinColumn(name = "EMPLOYEE_ID") })
    @NotFound(action=NotFoundAction.IGNORE)
    private Collection<Employee> employees = new ArrayList<Employee>();

    @Column(name="AWARD_TYPE")
    private String awardType;

    @Column(name="AWARD_DATE")
    private Date awardDate;

    @Column(name="AWARD_DETAILS")
    @Lob
    private String awardDetails;

    @Column(name="REMARK")
    private String remark;

@Entity
@Table(name="TB_EMPLOYEE")
public class Employee implements Serializable {

    @Id @GeneratedValue
    @Column(name="EMPLOYEE_ID")
    private long employeeID;

    @ManyToMany(
    cascade = CascadeType.ALL,
    mappedBy = "employees",
    targetEntity = Award.class
    )
    private Collection<Award> awards; //create the getter for this guy

始终查看examples in the reference以前，它会让你的生活变得更加轻松。 ;)