set

set是无序的不可重复，要想排序就实现Comparable接口

package com.cz.test.util.collection.set.sortedset;

import java.util.SortedSet;
import java.util.TreeSet;

public class SortedSetDemo {

/**
* @param args
*/
public static void main(String[] args) {
SortedSet<Player> players=new TreeSet<Player>();

Player tom=new Player("Tom", 1, 2, 3);
Player toms=new Player("Tom", 2, 2, 3);
Player jack=new Player("jack", 3, 2, 1);
Player rose=new Player("rose", 3, 1, 1);
Player jerry=new Player("jerry", 3, 2, 3);
Player merry=new Player("merry", 1, 1, 2);
Player chrils=new Player("chrils", 4, 2, 3);

players.add(chrils);
players.add(merry);
players.add(jerry);
players.add(rose);
players.add(jack);
players.add(tom);
players.add(toms);

for(Player player:players){
System.out.println("Player:"+player);
}

}

}

set取值

package com.cz.test.util.collection.set.sortedset;

import java.util.SortedSet;
import java.util.TreeSet;

public class TreeSetTest1 {

public static void main(String[] args) {
// TODO Auto-generated method stub
SortedSet set=new TreeSet();
set.add(2);
set.add(12);
set.add(4);
set.add(-4);
set.add(27);
set.add(17);

//第一个元素
System.out.println(set.first());
//最后一个元素
System.out.println(set.last());
//返回小于12的集合
System.out.println(set.headSet(12));
//返回大于6的集合
System.out.println(set.tailSet(6));
//返回大于-3小于5的子集
System.out.println(set.subSet(-3, 5));

}

}