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1
2
3 package com.db4odoc.f1.uuids;
4
5 import java.io.File  ;
6 import java.util.Date ;
7
8 import com.db4o.Db4o;
9 import com.db4o.ObjectContainer;
10 import com.db4o.ObjectSet;
11 import com.db4o.YapFile;
12 import com.db4o.ext.Db4oDatabase;
13 import com.db4o.ext.Db4oUUID;
14 import com.db4o.ext.ObjectInfo;
15 import com.db4o.foundation.TimeStampIdGenerator;
16 import com.db4o.query.Query;
17 import com.db4odoc.f1.Util;
18
19
20 public class UUIDExample extends Util {
21
22
23 public static void main(String [] args) {
24 testChangeIdentity();
25 setObjects();
26 testGenerateUUID();
27 }
28
30 private static String printSignature(byte[] signature){
31 String str = "";
32 for (int i = 0; i < signature.length; i++) {
33 str = str + signature[i];
34 }
35 return str;
36 }
37
39 public static void testChangeIdentity(){
40 new File (Util.YAPFILENAME).delete();
41 ObjectContainer oc = Db4o.openFile(Util.YAPFILENAME);
42 Db4oDatabase db;
43 byte[] oldSignature;
44 byte[] newSignature;
45 try {
46 db = oc.ext().identity();
47 oldSignature = db.getSignature();
48 System.out.println("oldSignature: " + printSignature(oldSignature));
49 ((YapFile)oc).generateNewIdentity();
50 } finally {
51 oc.close();
52 }
53 oc = Db4o.openFile(Util.YAPFILENAME);
54 try {
55 db = oc.ext().identity();
56 newSignature = db.getSignature();
57 System.out.println("newSignature: " + printSignature(newSignature));
58 } finally {
59 oc.close();
60 }
61
62 boolean same = true;
63
64 for (int i = 0; i < oldSignature.length; i++) {
65 if(oldSignature[i] != newSignature[i]){
66 same =false;
67 }
68 }
69
70 if (same){
71 System.out.println("Database signatures are identical");
72 } else {
73 System.out.println("Database signatures are different");
74 }
75 }
76
78 public static void setObjects(){
79 Db4o.configure().objectClass(Pilot.class).generateUUIDs(true);
80 new File (Util.YAPFILENAME).delete();
81 ObjectContainer oc = Db4o.openFile(Util.YAPFILENAME);
82 try {
83 Car car = new Car("BMW", new Pilot("Rubens Barrichello"));
84 oc.set(car);
85 } finally {
86 oc.close();
87 }
88 }
89
91 public static void testGenerateUUID(){
92 ObjectContainer oc = Db4o.openFile(Util.YAPFILENAME);
93 try {
94 Query query = oc.query();
95 query.constrain(Car.class);
96 ObjectSet result = query.execute();
97 Car car = (Car)result.get(0);
98 ObjectInfo carInfo = oc.ext().getObjectInfo(car);
99 Db4oUUID carUUID = carInfo.getUUID();
100 System.out.println("UUID for Car class are not generated:");
101 System.out.println("Car UUID: " + carUUID);
102
103 Pilot pilot = car.getPilot();
104 ObjectInfo pilotInfo = oc.ext().getObjectInfo(pilot);
105 Db4oUUID pilotUUID = pilotInfo.getUUID();
106 System.out.println("UUID for Pilot:");
107 System.out.println("Pilot UUID: " + pilotUUID);
108 System.out.println("long part: " + pilotUUID.getLongPart() +"; signature: " + printSignature(pilotUUID.getSignaturePart()));
109 long ms = TimeStampIdGenerator.idToMilliseconds(pilotUUID.getLongPart());
110 System.out.println("Pilot object was created: " + (new Date (ms)).toString());
111 Pilot pilotReturned = (Pilot) oc.ext().getByUUID(pilotUUID);
112 System.out.println("Pilot from UUID: " + pilotReturned);
113 } finally {
114 oc.close();
115 }
116 }
117 }
119 |
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