SpringBoot JPA @OneToOne @OneToMany @ManyToOne @ManyToMany

其中Role与Menu多对多

实体关系图.png

public class User implements Serializable {
    @Id
    private Long id;

    private String name;

    private String password;

    private String phone;

    private Integer age;

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

    @OneToOne(cascade = CascadeType.DETACH, fetch = FetchType.LAZY)
    @JoinColumn(name = "role_id", referencedColumnName = "id", insertable = false, updatable = false)
    private Role role;

    @OneToMany(mappedBy = "user",cascade = CascadeType.DETACH, fetch = FetchType.LAZY)
    private List<LoginLog> loginLogList;
}

@JsonIgnoreProperties(value = {"hibernateLazyInitializer", "handler"})
public class Role implements Serializable {
    @Id
    private Long id;

    private String name;

    private Long sort;

    @ManyToMany(fetch = FetchType.LAZY)
    @JoinTable(name = "sys_role_menu", joinColumns = {@JoinColumn(name = "roleId", referencedColumnName = "id")},
            inverseJoinColumns = {@JoinColumn(name = "menuId", referencedColumnName = "id")})
    private List<Menu> menuList;
}

public class Menu {
    @Id
    private Long id;

    private String name;

    private String url;

    private String icon;
}

public class RoleMenu {
    @Id
    private Long Id;

    private Long RoleId;

    private Long MenuId;

}

public class LoginLog implements Serializable {
    @Id
    private Long id;

    private String userId;

    private String log;

    private Date createTime;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "userId",insertable = false,updatable = false)
    private User user;

}

User和LoginLog配置了双向关联，使用中很容易造成循环引用问题，防止这种问题，网上一般做法是加上
@JsonIgnore注解，其实使用中可以不加此注解，而是尽量避免循环调用getUser()，getLoginLogList()方法。
直接将查询出来的实体类进行json序列化时，懒加载被激活，getUser()等被调用，此时会造成循环引用问题。