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1 package com.db4odoc.f1.indexes;
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.Query;
9 import com.db4odoc.f1.Util;
10
11
12 public class IndexedExample extends Util {
13 public static void main(String [] args){
14 IndexedExample.fillUpDB();
15 IndexedExample.noIndex();
16 IndexedExample.fullIndex();
17 IndexedExample.pilotIndex();
18 IndexedExample.pointsIndex();
19 }
20
22 public static void noIndex() {
23 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
24 try {
25 Query query = db.query();
26 query.constrain(Car.class);
27 query.descend("pilot").descend("points").constrain(new Integer (99));
28
29 long t1 = System.currentTimeMillis();
30 ObjectSet result = query.execute();
31 long t2 = System.currentTimeMillis();
32 long diff = t2 - t1;
33 System.out.println("Test 1: no indexes");
34 System.out.println("Execution time="+diff + " ms");
35 listResult(result);
36 }
37 finally {
38 db.close();
39 }
40 }
41
43 public static void fillUpDB(){
44 new File (Util.YAPFILENAME).delete();
45 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
46 try {
47 for (int i=0; i<10000;i++){
48 AddCar(db,i);
49 }
50 }
51 finally {
52 db.close();
53 }
54 }
55
57 public static void pilotIndex() {
58 Db4o.configure().objectClass(Car.class).objectField("pilot").indexed(true);
59 Db4o.configure().objectClass(Pilot.class).objectField("points").indexed(false);
60 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
61 try {
62 Query query = db.query();
63 query.constrain(Car.class);
64 query.descend("pilot").descend("points").constrain(new Integer (99));
65
66 long t1 = System.currentTimeMillis();
67 ObjectSet result = query.execute();
68 long t2 = System.currentTimeMillis();
69 long diff = t2 - t1;
70 System.out.println("Test 3: index on pilot");
71 System.out.println("Execution time="+diff + " ms");
72 listResult(result);
73 }
74 finally {
75 db.close();
76 }
77 }
78
80 public static void pointsIndex() {
81 Db4o.configure().objectClass(Car.class).objectField("pilot").indexed(false);
82 Db4o.configure().objectClass(Pilot.class).objectField("points").indexed(true);
83 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
84 try {
85 Query query = db.query();
86 query.constrain(Car.class);
87 query.descend("pilot").descend("points").constrain(new Integer (99));
88
89 long t1 = System.currentTimeMillis();
90 ObjectSet result = query.execute();
91 long t2 = System.currentTimeMillis();
92 long diff = t2 - t1;
93 System.out.println("Test 4: index on points");
94 System.out.println("Execution time="+diff + " ms");
95 listResult(result);
96 }
97 finally {
98 db.close();
99 }
100 }
101
103
104 public static void fullIndex() {
105 Db4o.configure().objectClass(Car.class).objectField("pilot").indexed(true);
106 Db4o.configure().objectClass(Pilot.class).objectField("points").indexed(true);
107 ObjectContainer db=Db4o.openFile(Util.YAPFILENAME);
108 try {
109 Query query = db.query();
110 query.constrain(Car.class);
111 query.descend("pilot").descend("points").constrain(new Integer (99));
112
113 long t1 = System.currentTimeMillis();
114 ObjectSet result = query.execute();
115 long t2 = System.currentTimeMillis();
116 long diff = t2 - t1;
117 System.out.println("Test 2: index on pilot and points");
118 System.out.println("Execution time="+diff + " ms");
119 listResult(result);
120 }
121 finally {
122 db.close();
123 }
124 }
125
127
128 private static void AddCar(ObjectContainer db, int points)
129 {
130 Car car = new Car("BMW");
131 car.setPilot(new Pilot("Tester", points));
132 db.set(car);
133 }
134
136 public static void listResult(ObjectSet result) {
137 System.out.println(result.size());
138 while(result.hasNext()) {
139 System.out.println(result.next());
140 }
141 }
142
144 }
145 |
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