Question

我有@ManyToMany关系的表格。当我尝试在表Employees中添加值时，我得到异常“分离的实体传递给持久化”。首先我在Outpost中创建了一些数据。如何添加员工？这是我的代码。

员工

@Entity
@Table(name = "Employees")
public class EmployeeEntity {

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE)
@Column(name = "employee_id", nullable = false)
private Integer employeeId;

@Column
private String name;

@Column
private String sureName;

@Column
private Long liferayUserId;

@Column
private String phone;

@Column
private String email;

@ManyToMany(cascade = { CascadeType.ALL })
@JoinTable(name = "Employee_Outpost", joinColumns = { @JoinColumn(name = "employee_id") }, inverseJoinColumns = { @JoinColumn(name = "outpost_id") })
private List<OutpostEntity> outposts;

前哨

@Entity
@Table(name = "Outpost")
public class OutpostEntity implements Serializable {

/**
 * 
 */
private static final long serialVersionUID = -7782359215536098452L;

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE)
@Column(name = "outpost_id", nullable = false)
private Integer outpostID;

@Column
private String province;

@Column
private String city;

@Column
private String postCode;

@Column
private String street;

@Column
private String phone;

@Column
private String openingHours;

@OneToMany(mappedBy = "outpostID", fetch = FetchType.EAGER)
private Set<ShipperEntity> shippers;

@ManyToMany(mappedBy = "outposts", cascade = CascadeType.MERGE, fetch = FetchType.EAGER)
private Set<EmployeeEntity> employees = new HashSet<EmployeeEntity>();

@OneToMany(mappedBy = "outpost", fetch = FetchType.LAZY)
private Set<AreaEntity> areas = new HashSet<AreaEntity>();

功能

EmployeeEntity employee = new EmployeeEntity(model.getName(),
model.getSurename(), model.getPhone(), model.getEmail(),
newUserId, outposts);
employeeJpaRepository.save(employee);

Answer 1

您遇到了PersistentObjectException，因为您的outposts处于分离状态。在调用employeeJpaRepository.merge(outposts);之前调用employeeJpaRepository.save(employee);会有所帮助。

merge()的介绍：

使用。将给定对象的状态复制到持久对象上相同的标识符如果当前没有持久化实例与会话相关联，它将被加载。返回持久性实例。如果给定实例未保存，请保存副本并返回它作为一个新的持久化实例。给定的实例不会成为与会话相关联。此操作级联到相关联如果关联是使用cascade =＆＃34; merge＆＃34;。
映射的实例

Hibernate ManyToMany在另一个表中存在时添加值

1 个答案: