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1 package com.db4odoc.f1.structured;
2
3 import java.io.File  ;
4
5 import com.db4o.Db4o;
6 import com.db4o.ObjectContainer;
7 import com.db4o.ObjectSet;
8 import com.db4o.query.Predicate;
9 import com.db4o.query.Query;
10
11
12 public class StructuredExample {
13 public final static String YAPFILENAME="formula1.yap";
14
15 public static void main(String [] args) {
16 new File (YAPFILENAME).delete();
17 ObjectContainer db=Db4o.openFile(YAPFILENAME);
18 try {
19 storeFirstCar(db);
20 storeSecondCar(db);
21 retrieveAllCarsQBE(db);
22 retrieveAllPilotsQBE(db);
23 retrieveCarByPilotQBE(db);
24 retrieveCarByPilotNameQuery(db);
25 retrieveCarByPilotProtoQuery(db);
26 retrievePilotByCarModelQuery(db);
27 updateCar(db);
28 updatePilotSingleSession(db);
29 updatePilotSeparateSessionsPart1(db);
30 db.close();
31 db=Db4o.openFile(YAPFILENAME);
32 updatePilotSeparateSessionsPart2(db);
33 db.close();
34 updatePilotSeparateSessionsImprovedPart1();
35 db=Db4o.openFile(YAPFILENAME);
36 updatePilotSeparateSessionsImprovedPart2(db);
37 db.close();
38 db=Db4o.openFile(YAPFILENAME);
39 updatePilotSeparateSessionsImprovedPart3(db);
40 deleteFlat(db);
41 db.close();
42 deleteDeepPart1();
43 db=Db4o.openFile(YAPFILENAME);
44 deleteDeepPart2(db);
45 deleteDeepRevisited(db);
46 }
47 finally {
48 db.close();
49 }
50 }
51
53 public static void storeFirstCar(ObjectContainer db) {
54 Car car1=new Car("Ferrari");
55 Pilot pilot1=new Pilot("Michael Schumacher",100);
56 car1.setPilot(pilot1);
57 db.set(car1);
58 }
59
61 public static void storeSecondCar(ObjectContainer db) {
62 Pilot pilot2=new Pilot("Rubens Barrichello",99);
63 db.set(pilot2);
64 Car car2=new Car("BMW");
65 car2.setPilot(pilot2);
66 db.set(car2);
67 }
68
70 public static void retrieveAllCarsQBE(ObjectContainer db) {
71 Car proto=new Car(null);
72 ObjectSet result=db.get(proto);
73 listResult(result);
74 }
75
77 public static void retrieveAllPilotsQBE(ObjectContainer db) {
78 Pilot proto=new Pilot(null,0);
79 ObjectSet result=db.get(proto);
80 listResult(result);
81 }
82
84 public static void retrieveAllPilots(ObjectContainer db) {
85 ObjectSet result=db.get(Pilot.class);
86 listResult(result);
87 }
88
90 public static void retrieveCarByPilotQBE(
91 ObjectContainer db) {
92 Pilot pilotproto=new Pilot("Rubens Barrichello",0);
93 Car carproto=new Car(null);
94 carproto.setPilot(pilotproto);
95 ObjectSet result=db.get(carproto);
96 listResult(result);
97 }
98
100 public static void retrieveCarByPilotNameQuery(
101 ObjectContainer db) {
102 Query query=db.query();
103 query.constrain(Car.class);
104 query.descend("pilot").descend("name")
105 .constrain("Rubens Barrichello");
106 ObjectSet result=query.execute();
107 listResult(result);
108 }
109
111 public static void retrieveCarByPilotProtoQuery(
112 ObjectContainer db) {
113 Query query=db.query();
114 query.constrain(Car.class);
115 Pilot proto=new Pilot("Rubens Barrichello",0);
116 query.descend("pilot").constrain(proto);
117 ObjectSet result=query.execute();
118 listResult(result);
119 }
120
122 public static void retrievePilotByCarModelQuery(ObjectContainer db) {
123 Query carquery=db.query();
124 carquery.constrain(Car.class);
125 carquery.descend("model").constrain("Ferrari");
126 Query pilotquery=carquery.descend("pilot");
127 ObjectSet result=pilotquery.execute();
128 listResult(result);
129 }
130
132 public static void retrieveAllPilotsNative(ObjectContainer db) {
133 ObjectSet results = db.query(new Predicate<Pilot>() {
134 public boolean match(Pilot pilot){
135 return true;
136 }
137 });
138 listResult(results);
139 }
140
142 public static void retrieveAllCars(ObjectContainer db) {
143 ObjectSet results = db.get(Car.class);
144 listResult(results);
145 }
146
148 public static void retrieveCarsByPilotNameNative(ObjectContainer db) {
149 final String pilotName = "Rubens Barrichello";
150 ObjectSet results = db.query(new Predicate<Car>() {
151 public boolean match(Car car){
152 return car.getPilot().getName().equals(pilotName);
153 }
154 });
155 listResult(results);
156 }
157
159 public static void updateCar(ObjectContainer db) {
160 ObjectSet result=db.query(new Predicate<Car>() {
161 public boolean match(Car car){
162 return car.getModel().equals("Ferrari");
163 }
164 });
165 Car found=(Car)result.next();
166 found.setPilot(new Pilot("Somebody else",0));
167 db.set(found);
168 result=db.query(new Predicate<Car>() {
169 public boolean match(Car car){
170 return car.getModel().equals("Ferrari");
171 }
172 });
173 listResult(result);
174 }
175
177 public static void updatePilotSingleSession(
178 ObjectContainer db) {
179 ObjectSet result=db.query(new Predicate<Car>() {
180 public boolean match(Car car){
181 return car.getModel().equals("Ferrari");
182 }
183 });
184 Car found=(Car)result.next();
185 found.getPilot().addPoints(1);
186 db.set(found);
187 result=db.query(new Predicate<Car>() {
188 public boolean match(Car car){
189 return car.getModel().equals("Ferrari");
190 }
191 });
192 listResult(result);
193 }
194
196 public static void updatePilotSeparateSessionsPart1(
197 ObjectContainer db) {
198 ObjectSet result=db.query(new Predicate<Car>() {
199 public boolean match(Car car){
200 return car.getModel().equals("Ferrari");
201 }
202 });
203 Car found=(Car)result.next();
204 found.getPilot().addPoints(1);
205 db.set(found);
206 }
207
209 public static void updatePilotSeparateSessionsPart2(
210 ObjectContainer db) {
211 ObjectSet result=db.query(new Predicate<Car>() {
212 public boolean match(Car car){
213 return car.getModel().equals("Ferrari");
214 }
215 });
216 listResult(result);
217 }
218
220 public static void updatePilotSeparateSessionsImprovedPart1() {
221 Db4o.configure().objectClass("com.db4o.f1.chapter2.Car")
222 .cascadeOnUpdate(true);
223 }
224
226 public static void updatePilotSeparateSessionsImprovedPart2(
227 ObjectContainer db) {
228 ObjectSet result=db.query(new Predicate<Car>() {
229 public boolean match(Car car){
230 return car.getModel().equals("Ferrari");
231 }
232 });
233 Car found=(Car)result.next();
234 found.getPilot().addPoints(1);
235 db.set(found);
236 }
237
239 public static void updatePilotSeparateSessionsImprovedPart3(
240 ObjectContainer db) {
241 ObjectSet result=db.query(new Predicate<Car>() {
242 public boolean match(Car car){
243 return car.getModel().equals("Ferrari");
244 }
245 });
246 listResult(result);
247 }
248
250 public static void deleteFlat(ObjectContainer db) {
251 ObjectSet result=db.query(new Predicate<Car>() {
252 public boolean match(Car car){
253 return car.getModel().equals("Ferrari");
254 }
255 });
256 Car found=(Car)result.next();
257 db.delete(found);
258 result=db.get(new Car(null));
259 listResult(result);
260 }
261
263 public static void deleteDeepPart1() {
264 Db4o.configure().objectClass("com.db4o.f1.chapter2.Car")
265 .cascadeOnDelete(true);
266 }
267
269 public static void deleteDeepPart2(ObjectContainer db) {
270 ObjectSet result=db.query(new Predicate<Car>() {
271 public boolean match(Car car){
272 return car.getModel().equals("BMW");
273 }
274 });
275 Car found=(Car)result.next();
276 db.delete(found);
277 result=db.query(new Predicate<Car>() {
278 public boolean match(Car car){
279 return true;
280 }
281 });
282 listResult(result);
283 }
284
286 public static void deleteDeepRevisited(ObjectContainer db) {
287 ObjectSet result=db.query(new Predicate<Pilot>() {
288 public boolean match(Pilot pilot){
289 return pilot.getName().equals("Michael Schumacher");
290 }
291 });
292 Pilot pilot=(Pilot)result.next();
293 Car car1=new Car("Ferrari");
294 Car car2=new Car("BMW");
295 car1.setPilot(pilot);
296 car2.setPilot(pilot);
297 db.set(car1);
298 db.set(car2);
299 db.delete(car2);
300 result=db.query(new Predicate<Car>() {
301 public boolean match(Car car){
302 return true;
303 }
304 });
305 listResult(result);
306 }
307
309 public static void listResult(ObjectSet result) {
310 System.out.println(result.size());
311 while(result.hasNext()) {
312 System.out.println(result.next());
313 }
314 }
315 }
317 |
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