import java.util.Arrays;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.TreeSet;
public class MainClass {
static void fill(Set s) {
s.addAll(Arrays.asList("one two three four five six seven".split(" ")));
}
public static void test(Set s) {
System.out.println(s.getClass().getName().replaceAll("\\w+\\.", ""));
fill(s);
System.out.println(s); // No duplicates!
s.addAll(s);
s.add("one");
System.out.println(s);
System.out.println("s.contains(\"one\"): " + s.contains("one"));
}
public static void main(String[] args) {
test(new HashSet());
test(new TreeSet());
test(new LinkedHashSet());
}
}
HashSet
[one, two, five, four, three, seven, six]
s.contains("one"): true
TreeSet
[five, four, one, seven, six, three, two]
s.contains("one"): true
LinkedHashSet
[one, two, three, four, five, six, seven]
s.contains("one"): true