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java - Hibernate:外键的列数错误

转载 作者:塔克拉玛干 更新时间:2023-11-03 05:19:40 24 4
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我已经在我的两个实体类 User 和 Permission 之间定义了多对多关系。 User 有一个由 username 和 countyId 组成的主键组合,而我的 Permission 表有一个常规的整数 Id。 UserPermission 表有三个外键作为其主键:username、countyId 和 permissionId。

由于这是一个遗留数据库,我将没有机会做正确的事 (™) 并在用户上创建一个整数主键。

我在 User.class 中定义了这样的多对多关系:

@ManyToMany(targetEntity=Permission.class, cascade={ CascadeType.PERSIST, CascadeType.MERGE } )
@JoinTable(name="tblUserPermission",
joinColumns = { @JoinColumn(name="username"), @JoinColumn(name="countyId") },
inverseJoinColumns = { @JoinColumn(name="permissionId") })
private Collection<Permission> permissions;

Permission.class 是这样说的:

@ManyToMany( cascade = {CascadeType.PERSIST, CascadeType.MERGE}, mappedBy = "permissions", targetEntity = User.class )
private Collection<User> users;

我认为这是要走的路,但是当我启动使用 Hibernate 3 的 Spring 上下文时,我得到:

Caused by: org.hibernate.AnnotationException: A Foreign key refering com.mydomain.data.entities.User from com.mydomain.data.entities.Permission has the wrong number of column. should be 1

我在注释中做错了什么?它应该是 2,而不是 1。


更新:

Arthur 建议我添加 referencedColumnName,但这给了我一个新的异常(exception):

Caused by: org.hibernate.AnnotationException: referencedColumnNames(username, countyId) of com.mydomain.data.entities.Permission.permissions referencing com.mydomain.data.entities.User not mapped to a single property

应他的要求,这里遵循代码:权限.Class:

package com.mydomain.data.entities;

import java.io.Serializable;
import java.util.Collection;
import javax.persistence.*;
import org.hibernate.annotations.ForeignKey;

@Entity
@Table(name = "tblPermission")
public class Permission extends PublishableEntityImpl implements Serializable, Cloneable {

private static final long serialVersionUID = 7155322069731920447L;

@Id
@Column(name = "PermissionId", length = 8, nullable = false)
private String PermissionId = "";

@ManyToOne(fetch=FetchType.LAZY)
@JoinColumn(name = "CountyId", nullable = false)
@ForeignKey(name="FK_CountyID")
private County county;

@Column(name = "Permission", nullable = true)
private Integer permission = 1;

@ManyToMany( cascade = {CascadeType.PERSIST, CascadeType.MERGE},
mappedBy = "Permissions",
targetEntity = Item.class )
private Collection<Item> items;

@ManyToMany( cascade = {CascadeType.PERSIST, CascadeType.MERGE},
mappedBy = "Permissions",
targetEntity = User.class )
private Collection<User> users;

/** Getters and Setters **/
}

和用户类

package com.mydomain.data.entities;

import java.util.*;
import java.io.Serializable;
import javax.persistence.*;
import org.hibernate.annotations.ForeignKey;
import org.hibernate.annotations.IndexColumn;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.GrantedAuthorityImpl;
import org.springframework.security.core.userdetails.UserDetails;

@Entity
@Table(name = "tblUser")
public class User extends PublishableEntityImpl implements Serializable, Cloneable {

@Id
@Column(name = "CountyId", nullable = false)
private Integer countyId;

@Id
@Column(name = "Username", length = 25, nullable = false)
private String username;

@ManyToOne(fetch=FetchType.LAZY)
@JoinColumn(name = "CountyId", nullable = false, insertable=false, updatable=false)
@ForeignKey(name="FK_CountyID")
private County county;

@Column(name = "Name", length = 50, nullable = true)
private String name;

@Column(name = "Password", length = 30, nullable = true)
private String password;

@Column(name = "Role", nullable = false)
private Integer role;

@ManyToMany(targetEntity=Permission.class,
cascade={ CascadeType.PERSIST, CascadeType.MERGE } )
@JoinTable(name="tblUserPermission",
joinColumns = { @JoinColumn(name="Username", referencedColumnName="Username"), @JoinColumn(name="CountyId", referencedColumnName="CountyId") },
inverseJoinColumns = { @JoinColumn(name="PermissionId", referencedColumnName="PermissionId") })
private Collection<Permission> permissions;

@OneToMany(fetch=FetchType.LAZY, mappedBy="county")
@IndexColumn(name="version")
private List<Version> versions;

/** Getters and setters **/
}

干杯

尼克

最佳答案

为了解决referencedColumnName异常

在用户放置

@ManyToMany(cascade={CascadeType.PERSIST, cascadeType.MERGE})
private Collection<Permission> permissions;

并在许可下

@ManyToMany(mappedBy="permissions")
@JoinTable(name="tblUserPermission",
joinColumns={@JoinColumn(name="permissionId", referencedColumnName="permissionId")},
inverseJoinColumns={
@JoinColumn(name="username", referencedColumnName="username"),
@JoinColumn(name="countyId", referencedColumnName="countyId")})
private Collection<User> users;

UserId 类

public class UserId implements Serializable {

private String username;

private Integer countyId;

// getter's and setter's

public boolean equals(Object o) {

if(o == null)
return false;

if(!(o instanceof UserId))
return false;

UserId id = (UserId) o;
if(!(getUsername().equals(id.getUsername()))
return false;

if(!(getCountyId().equals(id.getCountyId()))
return false;

return true;
}

public int hachcode() {
// hashcode
}

}

然后在User类中放置

@Entity
@Table(name="tblUser")
@IdClass(UserId.class)
public class User ... {

@Id
private String username;

@Id
private Integer countyId;

}

问候,

关于java - Hibernate:外键的列数错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/1483026/

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