只需要将@ManyToMany放在一个位置即可.

Just need to put @ManyToMany in one place only.

请在角色实体中删除@ManyToMany.您可以检查下面的链接，以便使用oracle数据库处理@ManyToMany.我希望这会有所帮助:

Please remove @ManyToMany in Role entity. You can check the link below in order to deal @ManyToMany using oracle database. I hope this is helpful:

https://gerardnico.com/jpa/many-to-many#oracle_database