Hibernate异常:identifier of an instance of 错误

今天写项目时，在使用hibernate封装的插入方法时，由于需要同时保存多个数据,导致出现identifier of an instance of

如下代码 :(由于最大最小分数不同所以需要插入两条数据)

ExamScoreDivide examScoreDivide=new ExamScoreDivide();
        ExamCourse examCourse=new ExamCourse();
        examCourse.setExamCourseId(examCourseId);

        Exam exam=new Exam();
        exam.setExamId(examId);

        examScoreDivide.setDivideId(StringUtil.getUuid());
        examScoreDivide.setMinScore(minScore1);
        examScoreDivide.setMaxScore(maxScore1);
        examScoreDivide.setExamCourse(examCourse);
        examScoreDivide.setExam(exam);
        examScoreDivide.setCreator(userInfo.getUserName());
        examScoreDivide.setCreateTime(DateUtil.currentDate());
        examScoreDivide.setDivideName(divideName);
        gradExamScoreDivideService.save(examScoreDivide);

examScoreDivide.setDivideId(StringUtil.getUuid());
        examScoreDivide.setMinScore(minScore2);
        examScoreDivide.setMaxScore(maxScore2);
        examScoreDivide.setExamCourse(examCourse);
        examScoreDivide.setExam(exam);
        examScoreDivide.setCreator(userInfo.getUserName());
        examScoreDivide.setCreateTime(DateUtil.currentDate());
        examScoreDivide.setDivideName(divideName);
        gradExamScoreDivideService.save(examScoreDivide);

但结果报该错误,后来知道了原因：

报错的原因是，在没有给对象examScoreDivide 分配初始的内存地址的时候，就进行对象生成，不管生成多少个，都是多个对象的内存指针指向一个内存地址，所以hibernate在存储时就会保存。放在内存里面每次new就等一个新的内存空间，所以不会报错。

解决后的代码：

ExamScoreDivide examScoreDivide=new ExamScoreDivide();
		ExamCourse examCourse=new ExamCourse();
		examCourse.setExamCourseId(examCourseId);

		Exam exam=new Exam();
		exam.setExamId(examId);

		examScoreDivide.setDivideId(StringUtil.getUuid());
		examScoreDivide.setMinScore(minScore1);
		examScoreDivide.setMaxScore(maxScore1);
		examScoreDivide.setExamCourse(examCourse);
		examScoreDivide.setExam(exam);
		examScoreDivide.setCreator(userInfo.getUserName());
		examScoreDivide.setCreateTime(DateUtil.currentDate());
		examScoreDivide.setDivideName(divideName);
		gradExamScoreDivideService.save(examScoreDivide);

		ExamScoreDivide examScoreDivide1=new ExamScoreDivide();
		ExamCourse examCourse1=new ExamCourse();
		examCourse1.setExamCourseId(examCourseId);

		Exam exam1=new Exam();
		exam1.setExamId(examId);

		examScoreDivide1.setDivideId(StringUtil.getUuid());
		examScoreDivide1.setMinScore(minScore2);
		examScoreDivide1.setMaxScore(maxScore2);
		examScoreDivide1.setExamCourse(examCourse1);
		examScoreDivide1.setExam(exam1);
		examScoreDivide1.setDivideName(divideName);
		examScoreDivide1.setCreator(userInfo.getUserName());
		examScoreDivide1.setCreateTime(DateUtil.currentDate());
		gradExamScoreDivideService.save(examScoreDivide1);