java自定义排序

 1 package GoodsSorting;

 2 //实例类

 3 public class GoodsParameter {

 4     // 价格

 5     private double price;

 6     // 收藏量

 7     private int favor;

 8     // 商品名称

 9     private String goodsname;

10     //无参构造

11     public GoodsParameter() {

12         super();

13     }

14     //带参构造

15     public GoodsParameter(String goodsname, double price, int favor) {

16         super();

17         this.price = price;

18         this.favor = favor;

19         this.goodsname = goodsname;

20     }

21     public double getPrice() {

22         return price;

23     }

24     public void setPrice(double price) {

25         this.price = price;

26     }

27     public int getFavor() {

28         return favor;

29     }

30     public void setFavor(int favor) {

31         this.favor = favor;

32     }

33     public String getGoodsname() {

34         return goodsname;

35     }

36     public void setGoodsname(String goodsname) {

37         this.goodsname = goodsname;

38     }

39     //重写tostring

40     @Override

41     public String toString() {

42         return "\t商品:" + getGoodsname() + "\t价格:" + getPrice() + "\t收藏量:"

43                 + getFavor() + "\n";

44     }

45 }

 1 package GoodsSorting;

 2 //排序工具类

 3 import java.util.Comparator;

 4 

 5 public class PriceSort implements Comparator<GoodsParameter> {

 6 

 7     public int compare(GoodsParameter o1, GoodsParameter o2) {

 8         int i=0;

 9         //按价格排序 正序

10         if ((o1.getPrice() - o2.getPrice()) > 0) {

11             i=1;

12         

13         }

14         else {

15             i=-1;

16             

17         }

18         return i;

19         

20     }

21 

22 }

 1 package GoodsSorting;

 2 

 3 import java.util.Comparator;

 4 

 5 public class FavorSort implements Comparator<GoodsParameter> {

 6 

 7     public int compare(GoodsParameter o1, GoodsParameter o2) {

 8         int i = 0;

 9         // 按收藏排序 正序

10         if (o1.getFavor()-o2.getFavor()<0) {  //逆序只需修改为>0

11             i=-1;

12         }

13         return i;

14     }

15 

16 }

 1 package GoodsSorting;

 2 

 3 import java.util.Comparator;

 4 

 5 public class NameSort implements Comparator<GoodsParameter> {

 6     public int compare(GoodsParameter o1, GoodsParameter o2) {

 7         int result = o1.getGoodsname().compareTo(o2.getGoodsname());

 8         return result;

 9     }

10 

11 }

 1 package GoodsSorting;

 2 //测试类

 3 import java.util.ArrayList;

 4 import java.util.Collections;

 5 import java.util.List;

 6 

 7 public class TestApp {

 8     public static void main(String[] args) {

 9         List<GoodsParameter> list = new ArrayList<GoodsParameter>();

10         list.add(new GoodsParameter("iphone", 5200, 110000));

11         list.add(new GoodsParameter("xiaomi", 1999, 50000));

12         list.add(new GoodsParameter("huawei", 1899, 60054));

13         list.add(new GoodsParameter("samsung", 4500, 80000));

14         list.add(new GoodsParameter("meizu", 1699, 125863));

15         // 排序前

16         System.out.println("原序:**********************");

17         System.out.println(list);

18 

19         Collections.sort(list, new PriceSort()); // 注意这里是collections

20         // 按价格排序后

21         System.out.println("价格排序:**********************");

22         System.out.println(list);

23         // 收藏量正序

24         System.out.println("收藏量排序:**********************");

25         Collections.sort(list, new FavorSort());

26         System.out.println(list);

27         // 名称正序

28         System.out.println("名称排序:**********************");

29         Collections.sort(list, new NameSort());

30         System.out.println(list);

31     }

32 }