我在LinkedList类中添加了引用类型的元素，使用Collections类中的reverseOrder方法反向排序，并迭代输出时报错，我想是不是我添加的是引用类型，程序并不能找出比较规则，所以我在下面又写了一个Comparator接口的实现类，想通过这个比较器设定一下规则，写完后又发现这个比较器作为参数不知道怎么传给LinkedList，因为LinkedList构造方法中没有传入Comparator类型的，不像TreeSet构造方法可以传Comparator类型。说的有点乱，请问怎么解决啊，可以复制代码运行一下，谢谢啦。
public class CollectonsTest {
public static void main(String[] args) {
LinkedList list = new LinkedList();
list.add(new Student(10));
list.add(new Student(20));
list.add(new Student(30));
list.add(new Student(40));
Comparator com = Collections.reverseOrder();
Collections.sort(list, com);
for(Iterator it = list.iterator();it.hasNext();){
Student stu = (Student)it.next();
System.out.println(stu.score);
}
}
}
class Student{
int score;
Student(int score){
this.score = score;
}
}
class MyComparator implements Comparator{
@Override
public int compare(Object o1, Object o2) {
Student s1 = (Student)o1;
Student s2 = (Student)o2;
return s1.score - s2.score;
}
}
------解决方案--------------------
- Java code
public class CollectonsTest { public static void main(String[] args) { LinkedList<Student> list = new LinkedList<Student>(); list.add(new Student(10)); list.add(new Student(20)); list.add(new Student(30)); list.add(new Student(40)); Comparator<Student> com = Collections.reverseOrder(); Collections.sort(list, com); for (Iterator<Student> it = list.iterator(); it.hasNext();) { Student stu = (Student) it.next(); System.out.println(stu.score); } }}class Student implements Comparable<Student>{ int score; Student(int score) { this.score = score; } @Override public int compareTo(Student s) { return this.score - s.score; }}