java:集合的自定义多重排序

问题：

有一个乱序的对象集合，要求先按对象的属性A排序（排序规则由业务确定，非A-Z或0-9的常规顺序），相同A属性的记录，按根据属性B排序（排序规则，同样由业务确定，非常规顺序） -前提：业务规则是明确的

示例：

FSUData对象定义

 1 package acc.test;
 2
 3 public class FSUData {
 4
 5     public FSUData(String airport, String fsuCode) {
 6         this.airport = airport;
 7         this.fsuCode = fsuCode;
 8     }
 9
10     /**
11      * 航站
12      */
13     private String airport;
14
15     /**
16      * FSU状态节点
17      */
18     private String fsuCode;
19
20     public String getAirport() {
21         return airport;
22     }
23
24     public void setAirport(String airport) {
25         this.airport = airport;
26     }
27
28     public String getFsuCode() {
29         return fsuCode;
30     }
31
32     public void setFsuCode(String fsuCode) {
33         this.fsuCode = fsuCode;
34     }
35
36     public String toString() {
37         return airport + "/" + fsuCode;
38     }
39
40 }

View Code

原始数据：

  [法兰克福/RCF, 法兰克福/DLV, 成都/DEP, 成都/RCS, 上海/DEP, 上海/RCF]

业务规则：

  航站排序规则：成都 -> 上海 -> 法兰克福

  FSU排序规则：RCS -> RCF -> TFD -> DEP -> DLV

要求排序后变成下面这样：

  [成都/RCS, 成都/DEP, 上海/RCF, 上海/DEP, 法兰克福/RCF, 法兰克福/DLV]

java代码： 

 1 package acc.test;
 2
 3 import java.util.ArrayList;
 4 import java.util.Collections;
 5 import java.util.Comparator;
 6 import java.util.HashMap;
 7 import java.util.List;
 8 import java.util.Map;
 9
10 import org.junit.Test;
11
12 public class FSUSortTest {
13
14     Map<String, Integer> airportDic = new HashMap<String, Integer>();
15     Map<String, Integer> fsuDic = new HashMap<String, Integer>();
16
17     @Test
18     public void test() {
19
20         // 先定义顺序规则
21         airportDic.put("成都", 1);
22         airportDic.put("上海", 2);
23         airportDic.put("法兰克福", 3);
24
25         fsuDic.put("RCS", 1);
26         fsuDic.put("RCF", 2);
27         fsuDic.put("TFD", 3);
28         fsuDic.put("DEP", 4);
29         fsuDic.put("DLV", 5);
30
31         // 建一个待排序的目标"数组"
32         List<FSUData> target = new ArrayList<FSUData>();
33
34         target.add(new FSUData("法兰克福", "RCF"));
35         target.add(new FSUData("法兰克福", "DLV"));
36
37         target.add(new FSUData("成都", "DEP"));
38         target.add(new FSUData("成都", "RCS"));
39
40         target.add(new FSUData("上海", "DEP"));
41         target.add(new FSUData("上海", "RCF"));
42
43         System.out.println("排序前：" + target);
44
45         // 排序
46         FsuComparator fsuComparator = new FsuComparator(airportDic, fsuDic);
47         Collections.sort(target, fsuComparator);
48
49         System.out.println("排序后：" + target);
50     }
51
52     private class FsuComparator implements Comparator<FSUData> {
53
54         Map<String, Integer> airportMap;
55         Map<String, Integer> fsuMap;
56
57         public FsuComparator(Map<String, Integer> airportMap,
58                 Map<String, Integer> fsuMap) {
59             this.airportMap = airportMap;
60             this.fsuMap = fsuMap;
61         }
62
63         public int compare(FSUData s1, FSUData s2) {
64
65             // 从顺序规则Map里，取出"排序值"
66             Integer airportOrder1 = airportMap.get(s1.getAirport());
67             Integer airportOrder2 = airportMap.get(s2.getAirport());
68
69             // 如果Airport相同，则比较FSUCode
70             if (airportOrder1 == airportOrder2) {
71                 Integer fsuOrder1 = fsuMap.get(s1.getFsuCode());
72                 Integer fsuOrder2 = fsuMap.get(s2.getFsuCode());
73                 return fsuOrder1.compareTo(fsuOrder2);
74             }
75
76             return airportOrder1.compareTo(airportOrder2);
77         }
78     }
79
80 }

View Code

思路：先将"业务排序规则" 转换成 "常规有序规则"，然后再利用Comparator接口实现比较