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1
2
3 package com.db4odoc.f1.staticfields;
4
5 import java.awt.Color  ;
6 import java.io.File ;
7
8 import com.db4o.Db4o;
9 import com.db4o.ObjectContainer;
10 import com.db4o.ObjectSet;
11
12
13 public class StaticFieldExample {
14 public final static String YAPFILENAME="formula1.yap";
15
16 public static void main(String [] args) {
17 setPilotsSimple();
18 checkPilots();
19 checkDatabaseFileSize();
20 setPilotsStatic();
22 checkPilots();
23 checkDatabaseFileSize();
24 updatePilots();
25 updatePilotCategories();
26 checkPilots();
27 deleteTest();
28 }
29
31 public static void setCar(){
32 new File (YAPFILENAME).delete();
33 ObjectContainer db=Db4o.openFile(YAPFILENAME);
34 try {
35 Car car = new Car();
36 car.color = Color.GREEN;
37 db.set(car);
38 } finally {
39 db.close();
40 }
41 }
42
44 public static void setPilotsSimple(){
45 System.out.println("In the default setting, static constants are not continously stored and updated.");
46 new File (YAPFILENAME).delete();
47 ObjectContainer db=Db4o.openFile(YAPFILENAME);
48 try {
49 db.set(new Pilot("Michael Schumacher",PilotCategories.WINNER));
50 db.set(new Pilot("Rubens Barrichello",PilotCategories.TALENTED));
51 } finally {
52 db.close();
53 }
54 }
55
57 public static void setPilotsStatic(){
58 System.out.println("The feature can be turned on for individual classes.");
59 Db4o.configure().objectClass("com.db4odoc.f1.staticfields.PilotCategories").persistStaticFieldValues();
60 new File (YAPFILENAME).delete();
61 ObjectContainer db=Db4o.openFile(YAPFILENAME);
62 try {
63 db.set(new Pilot("Michael Schumacher",PilotCategories.WINNER));
64 db.set(new Pilot("Rubens Barrichello",PilotCategories.TALENTED));
65 } finally {
66 db.close();
67 }
68 }
69
71 public static void checkPilots(){
72 ObjectContainer db=Db4o.openFile(YAPFILENAME);
73 try {
74 ObjectSet result = db.query(Pilot.class);
75 for(int x = 0; x < result.size(); x++){
76 Pilot pilot = (Pilot )result.get(x);
77 if (pilot.getCategory() == PilotCategories.WINNER){
78 System.out.println("Winner pilot: " + pilot);
79 } else if (pilot.getCategory() == PilotCategories.TALENTED){
80 System.out.println("Talented pilot: " + pilot);
81 } else {
82 System.out.println("Uncategorized pilot: " + pilot);
83 }
84 }
85 } finally {
86 db.close();
87 }
88 }
89
91 public static void updatePilots(){
92 System.out.println("Updating PilotCategory in pilot reference:");
93 ObjectContainer db=Db4o.openFile(YAPFILENAME);
94 try {
95 ObjectSet result = db.query(Pilot.class);
96 for(int x = 0; x < result.size(); x++){
97 Pilot pilot = (Pilot )result.get(x);
98 if (pilot.getCategory() == PilotCategories.WINNER){
99 System.out.println("Winner pilot: " + pilot);
100 PilotCategories pc = pilot.getCategory();
101 pc.testChange("WINNER2006");
102 db.set(pilot);
103 }
104 }
105 } finally {
106 db.close();
107 }
108 printCategories();
109 }
110
112 public static void updatePilotCategories(){
113 System.out.println("Updating PilotCategories explicitly:");
114 ObjectContainer db=Db4o.openFile(YAPFILENAME);
115 try {
116 ObjectSet result = db.query(PilotCategories.class);
117 for(int x = 0; x < result.size(); x++){
118 PilotCategories pc = (PilotCategories)result.get(x);
119 if (pc == PilotCategories.WINNER){
120 pc.testChange("WINNER2006");
121 db.set(pc);
122 }
123 }
124 } finally {
125 db.close();
126 }
127 printCategories();
128 System.out.println("Change the value back:");
129 db=Db4o.openFile(YAPFILENAME);
130 try {
131 ObjectSet result = db.query(PilotCategories.class);
132 for(int x = 0; x < result.size(); x++){
133 PilotCategories pc = (PilotCategories)result.get(x);
134 if (pc == PilotCategories.WINNER){
135 pc.testChange("WINNER");
136 db.set(pc);
137 }
138 }
139 } finally {
140 db.close();
141 }
142 printCategories();
143 }
144
146 public static void deleteTest(){
147 ObjectContainer db=Db4o.openFile(YAPFILENAME);
148 db.ext().configure().objectClass(Pilot.class).cascadeOnDelete(true);
149 try {
150 System.out.println("Deleting Pilots :");
151 ObjectSet result = db.query(Pilot.class);
152 for(int x = 0; x < result.size(); x++){
153 Pilot pilot = (Pilot )result.get(x);
154 db.delete(pilot);
155 }
156 printCategories();
157 System.out.println("Deleting PilotCategories :");
158 result = db.query(PilotCategories.class);
159 for(int x = 0; x < result.size(); x++){
160 db.delete(result.get(x));
161 }
162 printCategories();
163 } finally {
164 db.close();
165 }
166 }
167
169 public static void printCategories(){
170 ObjectContainer db=Db4o.openFile(YAPFILENAME);
171 try {
172 ObjectSet result = db.query(PilotCategories.class);
173 System.out.println("Stored categories: " + result.size());
174 for(int x = 0; x < result.size(); x++){
175 PilotCategories pc = (PilotCategories)result.get(x);
176 System.out.println("Category: "+pc);
177 }
178 } finally {
179 db.close();
180 }
181 }
182
184 public static void deletePilotCategories(){
185 printCategories();
186 ObjectContainer db=Db4o.openFile(YAPFILENAME);
187 try {
188 ObjectSet result = db.query(PilotCategories.class);
189 for(int x = 0; x < result.size(); x++){
190 PilotCategories pc = (PilotCategories)result.get(x);
191 db.delete(pc);
192 }
193 } finally {
194 db.close();
195 }
196 printCategories();
197 }
198
200 private static void checkDatabaseFileSize(){
201 System.out.println("Database file size: " + new File (YAPFILENAME).length() + "\n");
202 }
203 }
205 |
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