public class DicoPerformanceTest {
final static int NB_WORDS = 100000;
final static int NB_LOOKUPS = 1000;
/**
* @param args
*/
public static void main(String[] args) {
IDictionary dico1 = new ArrayListDictionary();
runExperiment("populate dico 1 (" + NB_WORDS + " words)", new
DictionaryRandomPopulator(dico1,
NB_WORDS));
runExperiment("look up dico 1 (" + NB_LOOKUPS + " search)",
new DictionaryLookupExperimenter(dico1, NB_LOOKUPS));
}
static void runExperiment(String name, Runnable r) {
System.out.println("start " + name);
long duration = System.currentTimeMillis();
r.run();
duration = System.currentTimeMillis() - duration;
System.out.println(name + " executed in " + duration + " ms");
}
//
// dictionary interface and implementation
//
static interface IDictionary {
void put(String word, String definition);
String getDefinition(String word);
}
static class ArrayListDictionary implements IDictionary {
List<String> _wordsList = new ArrayList<String>();
List<String> _definitionsList = new ArrayList<String>();
@Override
public void put(String word, String definition) {
_wordsList.add(word);
_definitionsList.add(definition);
}
@Override
public String getDefinition(String word) {
int index = _wordsList.indexOf(word);
if (index >= 0) {
_definitionsList.get(index);
}
// return null if word is not found in dictionary
return null;
}
}
//
// classes for experiment
//
static class WordGenerator {
public static String generate(int i) {
return "fake_word_" + i;
}
public static String generateRandom(Random random) {
return generate(random.nextInt(NB_WORDS));
}
}
static class DictionaryRandomPopulator implements Runnable {
private IDictionary _dictionary;
private int _size;
private Random _random = new Random(0);
DictionaryRandomPopulator(IDictionary dictionary, int size) {
super();
_dictionary = dictionary;
_size = size;
}
@Override
public void run() {
for (int i = 0; i < _size; i++) {
_dictionary.put(WordGenerator.generate(i),
generateDefinition(i));
}
}
private String generateDefinition(int i) {
return "fake definition for word " + i + " with random part: "
+ _random.nextInt();
}
}
static class DictionaryLookupExperimenter implements Runnable {
private IDictionary _dictionary;
private int _number;
private Random _random = new Random(0);
DictionaryLookupExperimenter(IDictionary dictionary, int number) {
super();
_dictionary = dictionary;
_number = number;
}
@Override
public void run() {
for (int i = 0; i < _number; i++) {
_dictionary
.getDefinition(WordGenerator.generateRandom(_random));
}
}
}
}