初始化器
Student stu1 = new Student();
Student stu2 = new Student();
Student stu3 = new Student();
ArrayList arrayList = new ArrayList() {
stu1, stu2, stu3,
};
Student stu1 = new Student();
Student stu2 = new Student();
Student stu3 = new Student();
ArrayList arrayList = new ArrayList() {
stu1, stu2, stu3,
};