// 學生list
    List<Student> students = new ArrayList<>();
    Student s1 = new Student("haha",12,"女");
    Student s2 = new Student("xixi",13,"男");
    Student s3 = new Student("guagua",14,"女");
    students.add(s1);
    students.add(s2);
    students.add(s3);

    // 把name為haha的學生放在最後面
    Student temp = new Student();
    boolean flag = false;

    for(int i = 0; i < students.size(); i++){
        Student student = students.get(i);
        if (student.getName().equals("haha")) {
            temp = student;
            flag = true;
            students.remove(i);

            break;
        }
    }

    if (flag) {
        students.add(temp);
    }

    for(int i = 0 ; i < students.size() ; i++) {
        Student s = students.get(i);
        System.out.println(s.getName() + s.getAge() + s.getSex());
        // xixi13男
        // guagua14女
        // haha12女
    }