java version of map benchmark

gistfile1.txt

package javabench;

import java.util.HashMap;
import java.util.Map;
// test other map types
//import java.util.LinkedHashMap;
//import java.util.TreeMap;
//import java.util.concurrent.ConcurrentHashMap;

public class MapTest {
	final static int ITERATIONS=1000000;
	final static String[] randomStrings=new String[]{
		"0000000000","1111111111","222222222","3333333333","4444444444","5555555555","6666666666","7777777777",
        "8888888888","9999999999","aaaaaaaaaa","bbbbbbbbbb","ccccccccc","dddddddddd","eeeeeeeeee","ffffffffff"
	};
	final static String[] randomStringsCopy=new String[randomStrings.length];
	static {
		for (int i=0; i<randomStrings.length; i++) {
			randomStringsCopy[i]=randomStrings[i].substring(0,1)+randomStrings[i].substring(1);
		}
	}
	static int testMap(int size) {
	  int x=0;
	  for (int i=0; i<ITERATIONS; i++) {
	    Map<String,Integer> map=new HashMap<>(); // try also LinkedHashMap, TreeMap etc
	    for (int j=0; j<size; j++) {
	      map.put(randomStrings[j],j);
	    }
	    
	    for (int j=0; j<size; j++) {
	       x|=map.get(randomStrings[j]); // !!! try change to randomStrings1 - get different timing
	    }
	  }
	  return x;
	}
	static void run(int size) {
	  int x=0;
	  long time=0; // saving result to print, to make sure nothing is optimized away miraculously
	  for (int i=0; i<3; i++) {
	    long start=System.currentTimeMillis();
	    x=testMap(size);
	    time=System.currentTimeMillis()-start;
	  }
	  System.out.println("Java HashMap" +" size="+size +" elapsed time="+time+" milliseconds => "+
	                     (1000000.0*time/(ITERATIONS*2*size))+" nanoseconds/operation "+" result="+x);
	}
	public static void	main(String[] arg) {
		for (int size: new int[]{6,8,10,12,14,16}) {
		     run(size);
		}
	}	
}