课程
/后端开发
/Java
/Hibernate初探之一对多映射
在往Grade的students属性中添加学生时报出空指针异常
2017-10-04
源自：Hibernate初探之一对多映射 2-6
正在回答
确实很不错，坚持学习。
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老铁666啊，我找了一上午的错，终于找到问题所在了
在有参构造器中还需对SET初始化，即：
public Grade(String gname, String gdesc) { super(); this.gname = gname; this.gdesc = gdesc; this.students = new HashSet<Student>(); }
举报
Hibernate中一对多关联映射配置，以及cascade和inverse属性作用
