Spring boot hibernate在从用户实体提取角色集时给出异常

Question

我在从数据库throw hibernate中的用户实体获取带有角色的结果集时遇到了问题，这就是我目前所拥有的：这里是数据库，我的sql数据库

package com.example.springboot.model;



import javax.persistence.*;
import java.util.HashSet;
import java.util.Set;

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

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name="userid")
private int id;

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

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

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

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

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

@ManyToMany(cascade = CascadeType.ALL)
@JoinTable(name = "user_role", joinColumns = @JoinColumn(name = "userid"), inverseJoinColumns = @JoinColumn(name = "roleid"))
private Set<Role> roles = new HashSet<>();

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getUsername() {
    return username;
}

public void setUsername(String username) {
    this.username = username;
}

public String getName() {
    return name;
}

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

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public String getDateCreated() {
    return dateCreated;
}

public void setDateCreated(String dateCreated) {
    this.dateCreated = dateCreated;
}

public Set<Role> getRoles() {
    return roles;
}

public void setRoles(Set<Role> roles) {
    this.roles = roles;
}

@Override
public String toString() {
    return "Userid: "+id;
}
}

和角色实体

package com.example.springboot.model;

import javax.persistence.*;

@Entity
@Table(name="role")
public class Role {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name="id")
private int id;

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

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

请帮帮我，我整天都在想办法解决这个问题，但没有希望。

null

Answer 1

根据您的模式，（在角色类中）应该是：

@Column(name="roleid")

..而不是：

@Column(name="id")