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 }