import java.util.BitSet; import java.util.HashSet; import java.util.Random; import java.util.Set; public class BitSetTest { /** * @param args */ public static void main(String[] args) { BitSet bm = new BitSet(); int randomVal = 1000000; for (int i = 0; i < 1000000; i++) { bm.set(new Random().nextInt(randomVal)); } BitSet bm2 = new BitSet(); for (int i = 0; i < 1000000; i++) { bm2.set(new Random().nextInt(randomVal)); } long s = System.currentTimeMillis(); bm2.and(bm); System.out.println(System.currentTimeMillis() - s); } }
import java.util.BitSet; import java.util.HashSet; import java.util.Random; import java.util.Set; public class SetTest { /** * @param args */ public static void main(String[] args) { HashSet bm=new HashSet(); int randomVal = 1000000; for(int i=0;i<1000000;i++){ bm.add(new Random().nextInt(randomVal)); } Set bm2=new HashSet(); for(int i=0;i<1000000;i++){ bm2.add(new Random().nextInt(randomVal)); } long s = System.currentTimeMillis(); bm.retainAll(bm2); System.out.println(bm.size()); System.out.println(bm2.size()); System.out.println(System.currentTimeMillis()-s); } }