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1 package com.db4o.f1.chapter21;
2
3 import java.io.File  ;
4 import java.util.Calendar ;
5
6 import com.db4o.Db4o;
7 import com.db4o.ObjectContainer;
8 import com.db4o.ObjectSet;
9 import com.db4o.f1.Util;
10 import com.db4o.query.Query;
11
12
13 public class IndexedExample extends Util {
14 public static void noIndex() {
15 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
16 try {
17 Query query = db.query();
18 query.constrain(Car.class);
19 query.descend("pilot").descend("points").constrain(new Integer (99));
20
21 long t1 = System.currentTimeMillis();
22 ObjectSet result = query.execute();
23 long t2 = System.currentTimeMillis();
24 long diff = t2 - t1;
25 System.out.println("Test 1: no indexes");
26 System.out.println("Execution time="+diff + " ms");
27 listResult(result);
28 }
29 finally {
30 db.close();
31 }
32 }
33
34 public static void fillUpDB(){
35 new File (Util.YAPFILENAME).delete();
36 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
37 try {
38 for (int i=0; i<10000;i++){
39 AddCar(db,i);
40 }
41 }
42 finally {
43 db.close();
44 }
45 }
46
47 public static void pilotIndex() {
48 Db4o.configure().objectClass(Car.class).objectField("pilot").indexed(true);
49 Db4o.configure().objectClass(Pilot.class).objectField("points").indexed(false);
50 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
51 try {
52 Query query = db.query();
53 query.constrain(Car.class);
54 query.descend("pilot").descend("points").constrain(new Integer (99));
55
56 long t1 = System.currentTimeMillis();
57 ObjectSet result = query.execute();
58 long t2 = System.currentTimeMillis();
59 long diff = t2 - t1;
60 System.out.println("Test 3: index on pilot");
61 System.out.println("Execution time="+diff + " ms");
62 listResult(result);
63 }
64 finally {
65 db.close();
66 }
67 }
68
69 public static void pointsIndex() {
70 Db4o.configure().objectClass(Car.class).objectField("pilot").indexed(false);
71 Db4o.configure().objectClass(Pilot.class).objectField("points").indexed(true);
72 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
73 try {
74 Query query = db.query();
75 query.constrain(Car.class);
76 query.descend("pilot").descend("points").constrain(new Integer (99));
77
78 long t1 = System.currentTimeMillis();
79 ObjectSet result = query.execute();
80 long t2 = System.currentTimeMillis();
81 long diff = t2 - t1;
82 System.out.println("Test 4: index on points");
83 System.out.println("Execution time="+diff + " ms");
84 listResult(result);
85 }
86 finally {
87 db.close();
88 }
89 }
90
91
92 public static void fullIndex() {
93 Db4o.configure().objectClass(Car.class).objectField("pilot").indexed(true);
94 Db4o.configure().objectClass(Pilot.class).objectField("points").indexed(true);
95 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
96 try {
97 Query query = db.query();
98 query.constrain(Car.class);
99 query.descend("pilot").descend("points").constrain(new Integer (99));
100
101 long t1 = System.currentTimeMillis();
102 ObjectSet result = query.execute();
103 long t2 = System.currentTimeMillis();
104 long diff = t2 - t1;
105 System.out.println("Test 2: index on pilot and points");
106 System.out.println("Execution time="+diff + " ms");
107 listResult(result);
108 }
109 finally {
110 db.close();
111 }
112 }
113
114
115 private static void AddCar(ObjectContainer db, int points)
116 {
117 Car car = new Car("BMW");
118 car.setPilot(new Pilot("Tester", points));
119 db.set(car);
120 }
121
122
123 }
124 |
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