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16 package org.apache.commons.collections.comparators;
17
18 import java.io.Serializable  ;
19 import java.util.Comparator ;
20 import java.util.LinkedList ;
21 import java.util.List ;
22
23 import junit.framework.Test;
24 import junit.framework.TestSuite;
25
26
33 public class TestComparatorChain extends AbstractTestComparator {
34
35 public TestComparatorChain(String testName) {
36 super(testName);
37 }
38
39 public static Test suite() {
40 return new TestSuite(TestComparatorChain.class);
41 }
42
43 public Comparator makeComparator() {
44 ComparatorChain chain = new ComparatorChain(new ColumnComparator(0));
45 chain.addComparator(new ColumnComparator(1),true); chain.addComparator(new ColumnComparator(2),false);
47 return chain;
48 }
49
50 public void testNoopComparatorChain() {
51 ComparatorChain chain = new ComparatorChain();
52 Integer i1 = new Integer (4);
53 Integer i2 = new Integer (6);
54 chain.addComparator(new ComparableComparator());
55
56 int correctValue = i1.compareTo(i2);
57 assertTrue("Comparison returns the right order",chain.compare(i1,i2) == correctValue);
58 }
59
60 public void testBadNoopComparatorChain() {
61 ComparatorChain chain = new ComparatorChain();
62 Integer i1 = new Integer (4);
63 Integer i2 = new Integer (6);
64 try {
65 chain.compare(i1,i2);
66 fail("An exception should be thrown when a chain contains zero comparators.");
67 } catch (UnsupportedOperationException e) {
68
69 }
70 }
71
72 public void testListComparatorChain() {
73 List list = new LinkedList ();
74 list.add(new ComparableComparator());
75 ComparatorChain chain = new ComparatorChain(list);
76 Integer i1 = new Integer (4);
77 Integer i2 = new Integer (6);
78
79 int correctValue = i1.compareTo(i2);
80 assertTrue("Comparison returns the right order",chain.compare(i1,i2) == correctValue);
81 }
82
83 public void testBadListComparatorChain() {
84 List list = new LinkedList ();
85 ComparatorChain chain = new ComparatorChain(list);
86 Integer i1 = new Integer (4);
87 Integer i2 = new Integer (6);
88 try {
89 chain.compare(i1,i2);
90 fail("An exception should be thrown when a chain contains zero comparators.");
91 } catch (UnsupportedOperationException e) {
92
93 }
94 }
95
96
97 public void testComparatorChainOnMinvaluedCompatator() {
98 ComparatorChain chain = new ComparatorChain();
101 chain.addComparator(
102 new Comparator () {
103 public int compare(Object a, Object b) {
104 int result = ((Comparable )a).compareTo(b);
105 if(result < 0) {
106 return Integer.MIN_VALUE;
107 } else if(result > 0) {
108 return Integer.MAX_VALUE;
109 } else {
110 return 0;
111 }
112 }
113 }, true);
114
115 assertTrue(chain.compare(new Integer (4), new Integer (5)) > 0);
116 assertTrue(chain.compare(new Integer (5), new Integer (4)) < 0);
117 assertTrue(chain.compare(new Integer (4), new Integer (4)) == 0);
118 }
119
120 public List getComparableObjectsOrdered() {
121 List list = new LinkedList ();
122 list.add(new PseudoRow(1,2,3));
125 list.add(new PseudoRow(2,3,5));
126 list.add(new PseudoRow(2,2,4));
127 list.add(new PseudoRow(2,2,8));
128 list.add(new PseudoRow(3,1,0));
129 list.add(new PseudoRow(4,4,4));
130 list.add(new PseudoRow(4,4,7));
131 return list;
132 }
133
134 public static class PseudoRow implements Serializable {
135
136 public int cols[] = new int[3];
137
138 public PseudoRow(int col1, int col2, int col3) {
139 cols[0] = col1;
140 cols[1] = col2;
141 cols[2] = col3;
142 }
143
144 public int getColumn(int colIndex) {
145 return cols[colIndex];
146 }
147
148 public String toString() {
149 StringBuffer buf = new StringBuffer ();
150 buf.append("[");
151 buf.append(cols[0]);
152 buf.append(",");
153 buf.append(cols[1]);
154 buf.append(",");
155 buf.append(cols[2]);
156 buf.append("]");
157 return buf.toString();
158 }
159
160 public boolean equals(Object o) {
161 if (!(o instanceof PseudoRow)) {
162 return false;
163 }
164
165 PseudoRow row = (PseudoRow) o;
166 if (getColumn(0) != row.getColumn(0)) {
167 return false;
168 }
169
170 if (getColumn(1) != row.getColumn(1)) {
171 return false;
172 }
173
174 if (getColumn(2) != row.getColumn(2)) {
175 return false;
176 }
177
178 return true;
179 }
180
181 }
182
183 public static class ColumnComparator implements Comparator ,Serializable {
184
185 protected int colIndex = 0;
186
187 public ColumnComparator(int colIndex) {
188 this.colIndex = colIndex;
189 }
190
191 public int compare(Object o1, Object o2) {
192
193 int col1 = ( (PseudoRow) o1).getColumn(colIndex);
194 int col2 = ( (PseudoRow) o2).getColumn(colIndex);
195
196 if (col1 > col2) {
197 return 1;
198 } else if (col1 < col2) {
199 return -1;
200 }
201
202 return 0;
203 }
204
205 public int hashCode() {
206 return colIndex;
207 }
208
209 public boolean equals(Object that) {
210 if(that instanceof ColumnComparator) {
211 return colIndex == ((ColumnComparator)that).colIndex;
212 } else {
213 return false;
214 }
215 }
216
217 private static final long serialVersionUID = -2284880866328872105L;
218 }
219 }
220 |
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