Java - Set

import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.TreeSet;

public class Test {

final static int LOOP_COUNT = 1000;
final static String STR_DATA = "abcdefghijklmnopqrstuvwxyz";
static Set<String> set;

public static void main(String[] args) {
warmUp();

set = new HashSet<String>();

showUsedTime();

set = new LinkedHashSet<String>();

showUsedTime();

set = new TreeSet<String>();

showUsedTime();
}

private static void warmUp() {
set = new HashSet<String>();

for (int i = 0; i < LOOP_COUNT; i++) {
set.add(STR_DATA + i);
}
}

private static void showUsedTime() {
String dummy = null;

long startTime = System.nanoTime();

for (int i = 0; i < LOOP_COUNT; i++) {
set.add(STR_DATA + i);
}

long endTime = System.nanoTime();
double elaspedTime = (endTime - startTime) / 1000000.0;

System.out.println("Add Time: " + elaspedTime);

startTime = System.nanoTime();

Iterator<String> iterator = set.iterator();

while (iterator.hasNext()) {
dummy = iterator.next();
}

endTime = System.nanoTime();
elaspedTime = (endTime - startTime) / 1000000.0;

System.out.println("Get Time: " + elaspedTime);
}
}