程序运行返回Exception in thread "main" java.lang.ClassCastException: Item cannot be cast to java.lang.Comparable.
求各位大哥大叔帮看看哪里出了问题。。。。
public class LinkListTest {

public static void main(String[] args) { SortedSet oo = new TreeSet<>(); oo.add(new Item("afang", 1011)); oo.add(new Item("fangjie", 1222)); oo.add(new Item("fangfang", 889)); System.out.println(oo); SortedSet sortedByDes = new TreeSet<>(new Comparator() { public int compare(Item a, Item b) { String desA = a.getDescription(); String desB = b.getDescription(); return desA.compareTo(desB); } }); sortedByDes.addAll(oo); System.out.println(sortedByDes); } } class Item { private String description; private int id; public Item(String aDes, int aId) { description = aDes; id = aId; } public String getDescription() { return description; }

}