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1
15 package org.josql.internal;
16
17 import java.util.List  ;
18 import java.util.ArrayList ;
19 import java.util.Comparator ;
20 import java.util.Map ;
21 import java.util.HashMap ;
22
23 import org.josql.expressions.Expression;
24
25 import org.josql.Query;
26
27 public class ListExpressionComparator implements Comparator
28 {
29
30 private List items = new ArrayList ();
31 private Query q = null;
32 private int size = 0;
33 private int count = 0;
34 private Exception exp = null;
35 private Object nullObj = new Object ();
36
37 private Map cache = new HashMap ();
38 private boolean caching = false;
39
40 public ListExpressionComparator (Query q,
41 boolean caching)
42 {
43
44 this.q = q;
45 this.caching = caching;
46
47 }
48
49 public int getCount ()
50 {
51
52 return this.count;
53
54 }
55
56 public boolean equals (Object o)
57 {
58
59 throw new UnsupportedOperationException ("Not supported for instances of: " +
60 this.getClass ().getName ());
61
62 }
63
64 public boolean isCaching ()
65 {
66
67 return this.caching;
68
69 }
70
71 public void setCaching (boolean b)
72 {
73
74 this.caching = b;
75
76 }
77
78 public void clearCache ()
79 {
80
81 this.cache.clear ();
82
83 }
84
85 public int ci (Object o1,
86 Object o2)
87 throws Exception
88 {
89
90 for (int i = 0; i < this.size; i++)
91 {
92
93 Item it = (Item) this.items.get (i);
94
95 this.q.setCurrentObject (o1);
96
97 Object eo1 = it.exp.getValue (o1,
98 this.q);
99
100 this.q.setCurrentObject (o2);
101
102 Object eo2 = it.exp.getValue (o2,
103 this.q);
104
105 int c = Utilities.compare (eo1,
107 eo2);
108
109 if (c == 0)
110 {
111
112 continue;
114
115 }
116
117 if (it.dir == 1)
119 {
120
121 c = -1 * c;
122
123 }
124
125 return c;
126
127 }
128
129 return 0;
130
131 }
132
133 public int cic (Object o1,
134 Object o2)
135 throws Exception
136 {
137
138 this.count++;
139
140 Map co = null;
141 boolean get = true;
142 Item it = null;
143 Object eo1 = null;
144 Object eo2 = null;
145
146 for (int i = 0; i < this.size; i++)
147 {
148
149 it = (Item) this.items.get (i);
150
151 eo1 = null;
152
153 get = true;
154
155 co = (Map ) cache.get (o1);
156
157 if (co == null)
158 {
159
160 co = new HashMap (this.size);
161
162 cache.put (o1,
163 co);
164
165 get = false;
166
167 }
168
169 if (get)
170 {
171
172 eo1 = co.get (it);
173
174 if (eo1 == this.nullObj)
175 {
176
177 eo1 = null;
178
179 }
180
181 }
182
183 if (eo1 == null)
184 {
185
186 this.q.setCurrentObject (o1);
187
188 eo1 = it.exp.getValue (o1,
189 this.q);
190
191 co.put (it,
192 eo1);
193
194 }
195
196 get = true;
197
198 eo2 = null;
199
200 co = (Map ) cache.get (o2);
201
202 if (co == null)
203 {
204
205 co = new HashMap (this.size);
206
207 cache.put (o2,
208 co);
209
210 get = false;
211
212 }
213
214 if (get)
215 {
216
217 eo2 = co.get (it);
218
219 }
220
221 if (eo2 == null)
222 {
223
224 this.q.setCurrentObject (o2);
225
226 eo2 = it.exp.getValue (o2,
227 this.q);
228
229 co.put (it,
230 eo2);
231
232 }
233
234 int c = Utilities.compare (eo1,
236 eo2);
237
238 if (c == 0)
239 {
240
241 continue;
243
244 }
245
246 if (it.dir == 1)
248 {
249
250 c = -1 * c;
251
252 }
253
254 return c;
255
256 }
257
258 return 0;
259
260 }
261
262 public int compare (Object o1,
263 Object o2)
264 {
265
266 try
267 {
268
269 if (this.caching)
270 {
271
272 return this.cic (o1,
273 o2);
274
275 } else {
276
277 return this.ci (o1,
278 o2);
279
280 }
281
282 } catch (Exception e) {
283
284 this.exp = e;
285
286 return 0;
287
288 }
289
290 }
291
292 public Exception getException ()
293 {
294
295 return this.exp;
296
297 }
298
299 public List getSortItems ()
300 {
301
302 return this.items;
303
304 }
305
306 public void addSortItem (Expression exp,
307 int dir)
308 {
309
310 Item it = new Item ();
311 it.dir = dir;
312 it.exp = exp;
313
314 this.items.add (it);
315
316 this.size = this.items.size ();
317
318 }
319
320 private class Item
321 {
322
323 public int dir = 0;
324 public Expression exp = null;
325
326 }
327
328 }
329 |
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