Java 学习排序

package com.src.hero;import java.util.ArrayList;import java.util.Collection;import java.util.Collections;import java.util.Comparator;import java.util.HashMap;import java.util.HashSet;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.TreeSet;/** * @author Hero * 2012-5-18 下午05:21:07 * java 简单的排序使用练习 */public class CollectionMy {/** * @author Hero 2012-5-18 下午02:10:10 * @param args * HashSet不保存重复值; */@SuppressWarnings({ "unused", "rawtypes", "unchecked" })private void Hashsetdeal(){Collection mycoll = new HashSet();mycoll.add("中国");mycoll.add("日本");mycoll.add("美国");mycoll.add("中国");mycoll.add("美国");System.out.println("--------------------------HashSet");for (Iterator it = mycoll.iterator(); it.hasNext();) {System.out.println(it.next().toString());}}/** * @author Hero * 2012-5-18 下午05:20:41 * 保存重复值 */@SuppressWarnings({ "unused", "rawtypes", "unchecked" })private void arrayList(){Collection mylist = new ArrayList();mylist.add("中国");mylist.add("日本");mylist.add("美国");mylist.add("中国");mylist.add("美国");System.out.println("--------------------------ArrayList");for (Iterator it = mylist.iterator(); it.hasNext();) {System.out.println(it.next().toString());}}@SuppressWarnings({ "unused", "rawtypes", "unchecked" })private void treeSet(){Person person1 = new Person(20);Person person2 = new Person(30);Person person3 = new Person(25);TreeSet tree2 = new TreeSet(new Mycoprate());tree2.add(person1);tree2.add(person2);tree2.add(person3);System.out.println("--------------------------TreeSet");for (Iterator it = tree2.iterator(); it.hasNext();) {Person person = (Person) it.next();System.out.println(person.getScore());}}    /**     * list排序通过重写Comparator方法     */private void deal() {List<Map<String, Object>> data = new ArrayList<Map<String, Object>>();for (int i = 0; i < 3; i++) {Map<String, Object> map = new HashMap<String, Object>();switch (i) {case 0:map.put("name", "zhangsan");map.put("age", 20);break;case 1:map.put("name", "lisi");map.put("age", 30);break;case 2:map.put("name", "wangwu");map.put("age", 25);break;default:break;}data.add(map);}Comparator<Map<String, Object>> agesort = new MycoprateList();Collections.sort(data, agesort);System.out.println("--------------------------List");for (int i = 0; i < data.size(); i++) {System.out.println(data.get(i));}}public static void main(String[] args) {// TODO Auto-generated method stubCollectionMy coll = new CollectionMy();coll.Hashsetdeal();coll.arrayList();coll.treeSet();coll.deal();}class MycoprateList implements Comparator<Map<String, Object>> {@Overridepublic int compare(Map<String, Object> o1, Map<String, Object> o2) {// TODO Auto-generated method stubreturn ((Integer) o1.get("age")).compareTo((Integer) o2.get("age"));}}class Person {private int score;public Person(int s) {this.score = s;}public int getScore() {return score;}public void setScore(int score) {this.score = score;}@Overridepublic String toString() {return "Person [score=" + score + "]";}}class Mycoprate implements Comparator {@Overridepublic int compare(Object o1, Object o2) {// TODO Auto-generated method stubPerson a = (Person) o1;Person b = (Person) o2;return ((Integer) a.getScore()).compareTo((Integer) b.getScore());}}//--------------------------HashSet//日本//美国//中国//--------------------------ArrayList//中国//日本//中国//美国//--------------------------TreeSet//20//25//30//--------------------------List//{age=20, name=zhangsan}//{age=25, name=wangwu}//{age=30, name=lisi}}