休眠：映射问题

Question

我遇到了休眠问题。 (((

!!! Image with Database Schema !!!

映射 （对于 getter's/setter's 我使用 lombok）

User.java

@Entity
@Table(name = "users")
public @Data class User
{

// Base Mapping

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "user_id")
@Getter @Setter Long user_id;   

@Column(name = "user_name")
private @Getter @Setter String user_name;

@Column(name = "login")
private @Getter @Setter String login;

@Column(name = "password")
private @Getter @Setter String password;

// Releations Mapping

// Releations With Project

@ManyToMany(cascade={CascadeType.ALL}) 
@JoinTable(name="users_on_projects",
        joinColumns=@JoinColumn(name="user_id"),
        inverseJoinColumns=@JoinColumn(name="project_id") )
        private @Getter @Setter  List<Project>  projects = new Vector();


@ManyToMany
@JoinTable(name="intervals",
        joinColumns=@JoinColumn(name="users_on_projects_id"),
        inverseJoinColumns=@JoinColumn(name="interval_id") )
        private  @Getter @Setter List<Interval> intervals = new Vector();
}

Project.java

@Entity
@Table(name = "projects")
public @Data class Project
{

// Base Mapping

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name ="project_id")
private @Getter @Setter  Long project_id;

@Column(name ="project_name")
private @Getter @Setter String project_name;


// Releations Mapping

// Releations With User

  @ManyToMany(cascade={CascadeType.ALL}) 
@JoinTable(name="users_on_projects",
        joinColumns=@JoinColumn(name="project_id"),
        inverseJoinColumns=@JoinColumn(name="user_id") )
  private @Getter @Setter  List<User>  users = new Vector();

@OneToMany
@JoinTable(name="intervals",
        joinColumns=@JoinColumn(name="users_on_projects_id"),
        inverseJoinColumns=@JoinColumn(name="interval_id") )
        private  @Getter @Setter List<Interval> intervals = new Vector();
}

Interval.java

@Entity
@Table(name = "intervals")
public class Interval
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "interval_id")
@Getter @Setter Long interval_id;

@Column(name ="start_time")
private @Setter @Getter 
            @Temporal(javax.persistence.TemporalType.TIMESTAMP)
            Date start_time;

@Column(name ="finish_time")
private @Setter @Getter 
        @Temporal(javax.persistence.TemporalType.TIMESTAMP)
        Date FinishTime;


@ManyToOne(cascade={CascadeType.ALL}) 
@JoinTable(name="users_on_projects",
        joinColumns=@JoinColumn(name="users_on_projects_id"),
        inverseJoinColumns=@JoinColumn(name="user_id") )
        private  @Getter @Setter User user;


@JoinTable(name="users_on_projects",
        joinColumns=@JoinColumn(name="users_on_projects_id"),
        inverseJoinColumns=@JoinColumn(name="project_id") )
        private  @Getter @Setter 
@ManyToOne
         Project project;


@ManyToOne(cascade = CascadeType.ALL)
@JoinColumn(name="interval_type_id")
private  @Getter @Setter IntervalType intervalType;

}

IntervalType.java

@Entity
@Table(name = "interval_type")
public class IntervalType
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "interval_type_id")
@Getter @Setter Long interval_type_id;

@Column(name = "interval_type_name")
private @Getter @Setter String interval_type_name;
}

我可以从任何表中读取任何数据，但不能写入区间表（（

错误信息是： *字段“users_on_projects_id”没有默认值* 并休眠生成此 SQL 代码： 插入区间 (finish_time, interval_type_id, start_time) 值 (?, ?, ?)

映射有什么问题？

Answer 1

您的映射看起来有点奇怪（但我可能理解错了）。我发现很奇怪的是这两种关系：

• 用户 -> 间隔
• 项目 -> 间隔

存储在相同的连接表“intervals”中，在这两种情况下，JoinColumn 都是“users_on_projects_id”。

对我来说，它看起来像是一个副本和过去的错误。