Course[] course ={new Course("3","离散数学"),new Course("4","汇编语言")};

courseToSelect.addAll(Arrays.asList(course));

Course temp3=(Course)coursesToSelect.get(2);

Course temp4=(Course)coursesToSelect.get(3);

System.out.println("添加了两门课程:"+temp3.id+":"+temp3.name+";"+temp4.id+":"+temp4.name);

Course[] course2 ={new Course("4","数学数学"),new Course("5","大学英语")};

courseToSelect.addAll(2,Arrays.asList(course2));

Course temp5=(Course)coursesToSelect.get(4);

Course temp6=(Course)coursesToSelect.get(5);

System.out.println("添加了两门课程:"+temp5.id+":"+temp5.name+";"+temp6.id+":"+temp6.name);

为什么在MyEclipse会报异常？？（其余代码与课程的代码都是一样的）