List delete collection elements

   @Data
    @AllArgsConstructor
    @NoArgsConstructor
    public static class Student {
    
        private String name;
        private String age;
    }

    public static void main(String[] args) {
    
        iteratorDelete();
// listDelete();
    }

    /** * list.remove() Delete will report an error  */
    private static void listDelete() {
    
        List<Student> cityList = setValue();
        System.out.println(cityList.size());
        for (Student student : cityList) {
    
            if(student.getAge().equals("xx")){
    
                cityList.remove(student);
            }
        }
        System.out.println(cityList.size());
    }


    /** * list Delete data delete using iterator  */
    private static void iteratorDelete() {
    
        List<Student> cityList = setValue();
        ListIterator<Student> iterator =cityList.listIterator();
        while (iterator.hasNext()) {
    
            Student student = iterator.next();
            if(student.getAge().equals("xx")){
    
                System.out.println(" What is deleted is the data of the collection , Yes iterator No impact ");
                iterator.remove();
            }
            System.out.println(" Length after deletion ："+cityList.size());
            int i = iterator.nextIndex();
            int previousIndex = iterator.previousIndex();
            System.out.println(student + "==" + i + "==" + previousIndex);

        }
        System.out.println(cityList.size());



    }
    private static List<Student> setValue(){
    
        List<Student> cityList = new ArrayList<Student>();
        cityList.add(new Student("xx", "xx"));
        cityList.add(new Student("qq", "qq"));
        cityList.add(new Student("ww", "ww"));
        cityList.add(new Student("ee", "ee"));
        cityList.add(new Student("rr", "rr"));
        cityList.add(new Student("tt", "tt"));
        return cityList;
    }