package javathreads.examples.ch14;

import java.util.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;

public class CollectionTest {
    static int nLoops;

    public static void main(String[] args) {

	nLoops = 10000;
        doTest(new Vector());
        doTest(new ModVector());
        doTest(new ArrayList());
        doTest(Collections.synchronizedList(new ArrayList()));
	nLoops = Integer.parseInt(args[0]);

        System.out.println("Starting synchronized vector test");
	cleanGC();
	Timestamp syncTS = new Timestamp();
        doTest(new Vector());
	syncTS.stop();
        System.out.println("Synchronized vector took " + syncTS);

        System.out.println("Starting unsynchronized vector test");
	cleanGC();
	Timestamp unsyncTS = new Timestamp();
        doTest(new ModVector());
	unsyncTS.stop();
        System.out.println("Unsynchronized vector took " + unsyncTS);

	double d = ((double) (syncTS.elapsedTime() - unsyncTS.elapsedTime())) /
		nLoops;
	System.out.println("Unsynchronized operation saves " + d + " " + syncTS.units() + " per call");


        System.out.println("Starting synchronized array list test");
	cleanGC();
	syncTS = new Timestamp();
        doTest(Collections.synchronizedList(new ArrayList()));
	syncTS.stop();
        System.out.println("Synchronized array list took " + syncTS);

        System.out.println("Starting unsynchronized array list test");
	cleanGC();
	unsyncTS = new Timestamp();
        doTest(new ArrayList());
	unsyncTS.stop();
        System.out.println("Unsynchronized aray list took " + unsyncTS);

	d = ((double) (syncTS.elapsedTime() - unsyncTS.elapsedTime())) /
		nLoops;
	System.out.println("Unsynchronized operation saves " + d + " " + syncTS.units() + " per call");
    }

    static void cleanGC() {
        System.gc();
        System.runFinalization();
        System.gc();
    }

    static void doTest(List l) {
	Integer n = new Integer(0);
	for (int i = 0; i < nLoops; i++)
	    l.add(n);
    }    
}