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1
28 package net.sf.jasperreports.engine.data;
29
30 import java.text.Collator  ;
31 import java.util.ArrayList ;
32 import java.util.Collections ;
33 import java.util.Comparator ;
34 import java.util.HashMap ;
35 import java.util.Iterator ;
36 import java.util.List ;
37 import java.util.Locale ;
38 import java.util.Map ;
39
40 import net.sf.jasperreports.engine.JRDataSource;
41 import net.sf.jasperreports.engine.JRException;
42 import net.sf.jasperreports.engine.JRField;
43 import net.sf.jasperreports.engine.JRRewindableDataSource;
44 import net.sf.jasperreports.engine.JRRuntimeException;
45 import net.sf.jasperreports.engine.JRSortField;
46
47
48
52 public class JRSortableDataSource implements JRRewindableDataSource
53 {
54
55
56
59 private List records = new ArrayList ();
60 private Iterator iterator = null;
61 private Object [] currentRecord = null;
62 private Map fieldIndexMap = new HashMap ();
63
64 protected Collator collator = null;
65
66
67
70 public JRSortableDataSource(JRDataSource ds, JRField[] fields, JRSortField[] sortFields, Locale locale) throws JRException
71 {
72 if (fields == null)
73 {
74 fields = new JRField[0];
76 }
77
78 if (sortFields == null)
79 {
80 sortFields = new JRSortField[0];
82 }
83
84
85 verifySortFields(fields, sortFields);
86
87 collator = Collator.getInstance(locale);
88
89 for(int i = 0; i < fields.length; i++)
90 {
91 fieldIndexMap.put(fields[i].getName(), new Integer (i));
92 }
93
94 int[] sortIndexes = new int[sortFields.length];
95 int[] sortOrders = new int[sortFields.length];
96 boolean[] collatorFlags = new boolean[sortFields.length];
97 for(int i = 0; i < sortFields.length; i++)
98 {
99 JRSortField sortField = sortFields[i];
100 sortIndexes[i] = ((Integer )fieldIndexMap.get(sortField.getName())).intValue();
101 sortOrders[i] = (JRSortField.SORT_ORDER_ASCENDING == sortField.getOrder() ? 1 : -1);
102
103 collatorFlags[i] = false;
104 for(int j = 0; j < fields.length; j++)
105 {
106 JRField field = fields[j];
107 if (sortField.getName().equals(field.getName()))
108 {
109 collatorFlags[i] = String .class.getName().equals(field.getValueClassName());
111 break;
112 }
113 }
114 }
115
116 if (ds != null)
117 {
118 while(ds.next())
119 {
120 Object [] record = new Object [fields.length];
121 for(int i = 0; i < fields.length; i++)
122 {
123 record[i] = ds.getFieldValue(fields[i]);
124 }
125 records.add(record);
126 }
127 }
128
129
130 Collections.sort(records, new DataSourceComparator(sortIndexes, sortOrders, collatorFlags));
131
132 iterator = records.iterator();
133 }
134
135
136
139 public boolean next()
140 {
141 boolean hasNext = false;
142
143 if (iterator != null)
144 {
145 hasNext = iterator.hasNext();
146
147 if (hasNext)
148 {
149 currentRecord = (Object [])iterator.next();
150 }
151 }
152
153 return hasNext;
154 }
155
156
157
160 public Object getFieldValue(JRField jrField)
161 {
162 Integer fieldIndex = (Integer )fieldIndexMap.get(jrField.getName());
163
164 if (fieldIndex == null)
165 {
166 throw new JRRuntimeException("Field \"" + jrField.getName() + "\" not found in sortable data source.");
167 }
168
169 return currentRecord[fieldIndex.intValue()];
170 }
171
172
173
176 public void moveFirst()
177 {
178 iterator = records.iterator();
179 }
180
181
182
185 public static void verifySortFields(JRField[] fields, JRSortField[] sortFields)
186 {
187 if (fields != null && sortFields != null)
188 {
189 for(int i = 0; i < sortFields.length; i++)
190 {
191 String sortFieldName = sortFields[i].getName();
192
193 boolean isFound = false;
194
195 int j = 0;
196 while (!isFound && j < fields.length)
197 {
198 isFound = sortFieldName.equals(fields[j].getName());
199 j++;
200 }
201
202 if (!isFound)
203 {
204 throw new JRRuntimeException("Sort field \"" + sortFieldName + "\" not found in the list of data source fields.");
205 }
206 }
207 }
208 }
209
210
211
214 class DataSourceComparator implements Comparator
215 {
216 int[] sortIndexes = null;
217 int[] sortOrders = null;
218 boolean[] collatorFlags = null;
219
220 public DataSourceComparator(int[] sortIndexes, int[] sortOrders, boolean[] collatorFlags)
221 {
222 this.sortIndexes = sortIndexes;
223 this.sortOrders = sortOrders;
224 this.collatorFlags = collatorFlags;
225 }
226
227 public int compare(Object arg1, Object arg2)
228 {
229 Object [] record1 = (Object [])arg1;
230 Object [] record2 = (Object [])arg2;
231
232 int ret = 0;
233
234 for(int i = 0; i < sortIndexes.length; i++)
235 {
236 int sortIndex = sortIndexes[i];
237 Comparable field1 = (Comparable )record1[sortIndex];
238 Comparable field2 = (Comparable )record2[sortIndex];
239
240 if (field1 == null)
241 {
242 ret = (field2 == null) ? 0 : -1;
243 }
244 else if (field2 == null)
245 {
246 ret = 1;
247 }
248 else
249 {
250 if (collatorFlags[i])
251 {
252 ret = collator.compare(field1, field2);
253 }
254 else
255 {
256 ret = field1.compareTo(field2);
257 }
258 }
259
260 ret = ret * sortOrders[i];
261
262 if (ret != 0)
263 {
264 return ret;
265 }
266 }
267
268 return ret;
269 }
270 }
271
272
273 }
274
275
276 |
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