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1
21 package com.db4o.test;
22
23 import java.util.*;
24
25 import com.db4o.*;
26 import com.db4o.query.*;
27
28 public class JdkComparatorSort {
29 private static class AscendingIdComparator implements Comparator {
30 public int compare(Object  first, Object second) {
31 return ((JdkComparatorSort)first)._id-((JdkComparatorSort)second)._id;
32 }
33 }
34
35 private static class DescendingIdComparator implements Comparator {
36 public int compare(Object first, Object second) {
37 return ((JdkComparatorSort)second)._id-((JdkComparatorSort)first)._id;
38 }
39 }
40
41 private static class OddEvenIdComparator implements Comparator {
42 public int compare(Object first, Object second) {
43 int idA=((JdkComparatorSort)first)._id;
44 int idB=((JdkComparatorSort)second)._id;
45 int modA=idA%2;
46 int modB=idB%2;
47 if(modA!=modB) {
48 return modA-modB;
49 }
50 return idA-idB;
51 }
52 }
53
54 private static class AscendingNameComparator implements Comparator {
55 public int compare(Object first, Object second) {
56 return ((JdkComparatorSort)first)._name.compareTo(((JdkComparatorSort)second)._name);
57 }
58 }
59
60 private static class SmallerThanThreePredicate extends Predicate {
61 public boolean match(JdkComparatorSort candidate) {
62 return candidate._id<3;
63 }
64 }
65
66 public int _id;
67 public String _name;
68
69 public JdkComparatorSort() {
70 this(0,null);
71 }
72
73 public JdkComparatorSort(int id, String name) {
74 this._id = id;
75 this._name = name;
76 }
77
78 public void store() {
79 for(int i=0;i<4;i++) {
80 Test.store(new JdkComparatorSort(i,String.valueOf(3-i)));
81 }
82 }
83
84 public void testByIdAscending() {
85 assertIdOrder(new AscendingIdComparator(),new int[]{0,1,2,3});
86 }
87
88 public void testByIdAscendingConstrained() {
89 Query query=Test.query();
90 query.constrain(getClass());
91 query.descend("_id").constrain(new Integer (3)).smaller();
92 assertIdOrder(query,new AscendingIdComparator(),new int[]{0,1,2});
93 }
94
95 public void testByIdAscendingNQ() {
96 ObjectSet result=Test.objectContainer().query(new SmallerThanThreePredicate(),new AscendingIdComparator());
97 assertIdOrder(result,new int[]{0,1,2});
98 }
99
100 public void testByIdDescending() {
101 assertIdOrder(new DescendingIdComparator(),new int[]{3,2,1,0});
102 }
103
104 public void testByIdDescendingConstrained() {
105 Query query=Test.query();
106 query.constrain(getClass());
107 query.descend("_id").constrain(new Integer (3)).smaller();
108 assertIdOrder(query,new DescendingIdComparator(),new int[]{2,1,0});
109 }
110
111 public void testByIdDescendingNQ() {
112 ObjectSet result=Test.objectContainer().query(new SmallerThanThreePredicate(),new DescendingIdComparator());
113 assertIdOrder(result,new int[]{2,1,0});
114 }
115
116 public void testByIdOddEven() {
117 assertIdOrder(new OddEvenIdComparator(),new int[]{0,2,1,3});
118 }
119
120 public void testByIdOddEvenConstrained() {
121 Query query=Test.query();
122 query.constrain(getClass());
123 query.descend("_id").constrain(new Integer (3)).smaller();
124 assertIdOrder(query,new OddEvenIdComparator(),new int[]{0,2,1});
125 }
126
127 public void testByIdOddEvenNQ() {
128 ObjectSet result=Test.objectContainer().query(new SmallerThanThreePredicate(),new OddEvenIdComparator());
129 assertIdOrder(result,new int[]{0,2,1});
130 }
131
132 public void testByNameAscending() {
133 assertIdOrder(new AscendingNameComparator(),new int[]{3,2,1,0});
134 }
135
136 public void testByNameAscendingConstrained() {
137 Query query=Test.query();
138 query.constrain(getClass());
139 query.descend("_id").constrain(new Integer (3)).smaller();
140 assertIdOrder(query,new AscendingNameComparator(),new int[]{2,1,0});
141 }
142
143 public void testByNameAscendingNQ() {
144 ObjectSet result=Test.objectContainer().query(new SmallerThanThreePredicate(),new AscendingNameComparator());
145 assertIdOrder(result,new int[]{2,1,0});
146 }
147
148 private void assertIdOrder(Comparator comparator,int[] ids) {
149 Query query=Test.query();
150 query.constrain(getClass());
151 assertIdOrder(query,comparator,ids);
152 }
153
154 private void assertIdOrder(Query query,Comparator comparator,int[] ids) {
155 query.sortBy(comparator);
156 ObjectSet result=query.execute();
157 assertIdOrder(result,ids);
158 }
159
160 private void assertIdOrder(ObjectSet result,int[] ids) {
161 Test.ensureEquals(ids.length,result.size());
162 for (int idx = 0; idx < ids.length; idx++) {
163 Test.ensureEquals(ids[idx], ((JdkComparatorSort)result.next())._id);
164 }
165 }
166
167 public static void main(String [] args) {
168 Test.run(JdkComparatorSort.class);
169 }
170 }
171 |
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