Question

我有两个实体项目和用户。项目具有2个字段：所有者和创建者，它们是用户对象。这些字段由@OneToOne（cascade = CascadeType.ALL）映射。

我可以与其他所有者和创建者一起保存项目。当我尝试使用相同的所有者和创建者保存Project对象时，收到以下错误消息：

已经有一个具有相同标识符值的不同对象与会话相关联

原因是Hibernate使用CascadeType.ALL保存。当2个字段引用表中的同一对象/行时，是否可以使用Cascade保存此Project对象？

项目实体：

/api

}

用户实体：

server

ProjectRepository：

package com.entity;

import java.sql.Timestamp;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.OneToOne;
import javax.persistence.Table;

@Entity
@Table(name="project")
public class Project {
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="project_id")
private int projectId;

@Column(name="number")
private int number;

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

@OneToOne(cascade=CascadeType.ALL)
@JoinColumn(name="owner_id")
private User owner;

@OneToOne(cascade=CascadeType.ALL)
@JoinColumn(name="creator_id")
private User creator;

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

@Column(name="start_time")
private Timestamp startTime;

@Column(name="end_time")
private Timestamp endTime;

public Project() {

}

public int getProjectId() {
    return projectId;
}

public void setProjectId(int projectId) {
    this.projectId = projectId;
}

public int getNumber() {
    return number;
}

public void setNumber(int number) {
    this.number = number;
}

public String getName() {
    return name;
}

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

public User getOwner() {
    return owner;
}

public void setOwner(User owner) {
    this.owner = owner;
}

public User getCreator() {
    return creator;
}

public void setCreator(User creator) {
    this.creator = creator;
}

public String getDescription() {
    return description;
}

public void setDescription(String description) {
    this.description = description;
}

public Timestamp getStartTime() {
    return startTime;
}

public void setStartTime(Timestamp startTime) {
    this.startTime = startTime;
}

public Timestamp getEndTime() {
    return endTime;
}

public void setEndTime(Timestamp endTime) {
    this.endTime = endTime;
}

休眠-映射-具有相同标识符值的其他对象已与会话关联

0 个答案: