遍历List，删除其中元素的正确做法

public class People{
public int age;
public String gender;
public People(int age,String gender){
this.age = age;
this.gender = gender;
}

public static void main(String[] args) {
List<People> lists = new ArrayList<People>();
People p1 = new People(13, "Woman");
lists.add(p1);
People p2 = new People(24, "Man");
lists.add(p2);
People p3 = new People(25,"Woman");
lists.add(p3);
People p4 = new People(34,"Man");
lists.add(p4);

for(Iterator<People> it = lists.iterator();it.hasNext();){
People people = it.next();
if(people.age>30){
it.remove();//注意这里是it不是lists
}
}
System.out.println(lists.size());
}
}