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Java > Open Source Codes > com > db4odoc > f1 > blobs > BlobExample


1 /* Copyright (C) 2004 - 2006 db4objects Inc. http://www.db4o.com */
2
3 package com.db4odoc.f1.blobs;
4
5 import java.io.File JavaDoc;
6
7 import com.db4o.Db4o;
8 import com.db4o.ObjectContainer;
9 import com.db4o.ObjectSet;
10 import com.db4o.query.Query;
11
12
13
14 public class BlobExample {
15     public final static String JavaDoc YAPFILENAME="formula1.yap";
16     public static void main(String JavaDoc[] args) {
17         storeCars();
18         retrieveCars();
19     }
20     // end main
21

22       public static void storeCars() {
23           new File JavaDoc(YAPFILENAME).delete();
24           ObjectContainer db=Db4o.openFile(YAPFILENAME);
25            try {
26                 Car car1=new Car("Ferrari");
27                 db.set(car1);
28                 storeImage(car1);
29                 Car car2=new Car("BMW");
30                 db.set(car2);
31                 storeImage(car2);
32            } finally {
33               db.close();
34             }
35       }
36       // end storeCars
37

38       public static void storeImage(Car car) {
39         CarImage img = car.getImage();
40         try {
41             img.readFile();
42         } catch (java.io.IOException JavaDoc ex) {
43             System.out.println(ex.getMessage());
44         }
45     }
46
47     // end storeImage
48

49       public static void retrieveCars() {
50           ObjectContainer db=Db4o.openFile(YAPFILENAME);
51            try {
52                Query query = db.query();
53                query.constrain(Car.class);
54                ObjectSet result = query.execute();
55                getImages(result);
56            } finally {
57               db.close();
58             }
59       }
60       // end retrieveCars
61

62       private static void getImages(ObjectSet result){
63           while(result.hasNext()) {
64                 Car car = (Car)(result.next());
65                 System.out.println(car);
66                 CarImage img = car.getImage();
67                 try {
68                     img.writeFile();
69                 } catch (java.io.IOException JavaDoc ex){
70                     System.out.print(ex.getMessage());
71                 }
72             }
73       }
74       // end getImages
75
}
76
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