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1
19 package gnu.trove.benchmark;
20
21 import gnu.trove.*;
22
23 import java.util.ArrayList  ;
24 import java.util.HashMap ;
25 import java.util.HashSet ;
26 import java.util.LinkedList ;
27
28 public class MemoryUsage {
29 public static long sizeOf(Creator c) {
30 long size= 0;
31 Object [] objects = new Object [100];
32 try {
33 Object primer = c.create();
34 long startingMemoryUse = getUsedMemory();
35 for (int i = 0; i < objects.length; i++) {
36 objects[i] = c.create();
37 }
38 long endingMemoryUse = getUsedMemory();
39 float approxSize = (endingMemoryUse -
40 startingMemoryUse) / 100f;
41 size = Math.round(approxSize);
42 } catch (Exception e) {
43 e.printStackTrace();
44 }
45 return size;
46 }
47
48 private static long getUsedMemory() {
49 gc();
50 long totalMemory = Runtime.getRuntime().totalMemory();
51 gc();
52 long freeMemory = Runtime.getRuntime().freeMemory();
53 long usedMemory = totalMemory - freeMemory;
54 return usedMemory;
55 }
56
57 private static void gc() {
58 try {
59 System.gc();
60 Thread.currentThread().sleep(100);
61 System.runFinalization();
62 Thread.currentThread().sleep(100);
63 System.gc();
64 Thread.currentThread().sleep(100);
65 System.runFinalization();
66 Thread.currentThread().sleep(100);
67 } catch (Exception e) {
68 e.printStackTrace();
69 }
70 }
71
72 public static void main(String [] args) {
73 try {
74 MemoryComparator set =
75 new MemoryComparator(new TroveSetCreator(),
76 new JavasoftSetCreator(),
77 "Compare size of Set implementation: 1,000 Integer objects measured in bytes");
78 set.compare();
79 set = null;
80 MemoryComparator list =
81 new MemoryComparator(new TroveListCreator(),
82 new JavasoftListCreator(),
83 "Compare size of LinkedList implementation: 1,000 TLinkableAdaptor objects measured in bytes");
84 list.compare();
85 list = null;
86 MemoryComparator list2 =
87 new MemoryComparator(new TroveIntArrayListCreator(),
88 new JavasoftIntegerArrayListCreator(),
89 "Compare size of int/IntegerArrayList implementation: 1,000 ints measured in bytes");
90 list2.compare();
91 list2 = null;
92
93 MemoryComparator map =
94 new MemoryComparator(new TroveMapCreator(),
95 new JavasoftMapCreator(),
96 "Compare size of Map implementation: 1,000 Integer->Integer mappings measured in bytes");
97 map.compare();
98 } catch (Exception e) {
99 e.printStackTrace();
100 }
101 System.exit(0);
102 }
103
104 static class MemoryComparator {
105 Creator trove, javasoft;
106 String description;
107 MemoryComparator(Creator trove,
108 Creator javasoft,
109 String description) {
110 this.trove = trove;
111 this.javasoft = javasoft;
112 this.description = description;
113 }
114
115 public void compare() {
116 gc();
117 long j = sizeOf(javasoft);
118 gc();
119 long t = sizeOf(trove);
120
121 long p = Math.round(t * 100 / j * 100) / 100;
122
123 System.out.println("--------------------------");
124 System.out.println(description);
125 System.out.println("javasoft: " + j);
126 System.out.println("trove: " + t);
127 System.out.println("trove's collection requires " + p + "% of the memory needed by javasoft's collection");
128 }
129 }
130
131 interface Creator {
132 Object create();
133 }
134
135 static class TroveIntArrayListCreator implements Creator {
136 public Object create() {
137 TIntArrayList list = new TIntArrayList();
138 for (int i = 0; i < 1000; i++) {
139 list.add(i);
140 }
141 list.trimToSize();
142 return list;
143 }
144 }
145
146 static class JavasoftIntegerArrayListCreator implements Creator {
147 public Object create() {
148 ArrayList list = new ArrayList ();
149 for (int i = 0; i < 1000; i++) {
150 Integer x = new Integer (i);
151 list.add(x);
152 }
153 list.trimToSize();
154 return list;
155 }
156 }
157
158 static class TroveMapCreator implements Creator {
159 public Object create() {
160 THashMap map = new THashMap();
161 for (int i = 0; i < 1000; i++) {
162 Integer x = new Integer (i);
163 map.put(x,x);
164 }
165 return map;
166 }
167 }
168
169 static class JavasoftMapCreator implements Creator {
170 public Object create() {
171 HashMap map = new HashMap ();
172 for (int i = 0; i < 1000; i++) {
173 Integer x = new Integer (i);
174 map.put(x,x);
175 }
176 return map;
177 }
178 }
179
180 static class TroveSetCreator implements Creator {
181 public Object create() {
182 THashSet map = new THashSet();
183 for (int i = 0; i < 1000; i++) {
184 Integer x = new Integer (i);
185 map.add(x);
186 }
187 return map;
188 }
189 }
190
191 static class JavasoftSetCreator implements Creator {
192 public Object create() {
193 HashSet map = new HashSet ();
194 for (int i = 0; i < 1000; i++) {
195 Integer x = new Integer (i);
196 map.add(x);
197 }
198 return map;
199 }
200 }
201
202 static class TroveListCreator implements Creator {
203 public Object create() {
204 TLinkedList list = new TLinkedList();
205 for (int i = 0; i < 1000; i++) {
206 TLinkableAdapter a = new TLinkableAdapter();
207 list.add(a);
208 }
209 return list;
210 }
211 }
212
213 static class JavasoftListCreator implements Creator {
214 public Object create() {
215 LinkedList list = new LinkedList ();
216 for (int i = 0; i < 1000; i++) {
217 TLinkableAdapter a = new TLinkableAdapter();
218 list.add(a);
219 }
220 return list;
221 }
222 }
223 }
224 |
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