Test.java

package kz.kaznu.counter;

import com.google.common.base.Stopwatch;
import kz.kaznu.counter.commons.utils.LoggerEnabler;
import kz.kaznu.counter.commons.utils.Timer;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.Random;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;

/**
 * User: Sanzhar Aubakirov
 * Date: 8/16/16
 */
public class Test {


    public static final int NUMBER_OF_TIMES_TO_TEST = 1000;
    public static long timeDirectDelete = 0;
    public static long timeCreateNewArray = 0;
    private final Random random = new Random();

    @org.junit.Test
    public void test() throws Exception {

        for (int i = 0; i < NUMBER_OF_TIMES_TO_TEST; i++) {
            testDeleteOneElement();
        }

        System.out.println(timeDirectDelete/NUMBER_OF_TIMES_TO_TEST+ "\t" + timeCreateNewArray/NUMBER_OF_TIMES_TO_TEST);
    }

    public void testDeleteOneElement() throws Exception {
        final ArrayList<Double> array1 = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            array1.add(random.nextDouble() * 100000);
        }
        timeDirectDelete += executeVoidFunctionWithTimer(() -> deleteFromArray(array1));

        final ArrayList<Double> array2 = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            array2.add(random.nextDouble() * 100000);
        }
        timeCreateNewArray += executeVoidFunctionWithTimer(() -> createNewArrayWithoutElement(array2));

    }

    private Void deleteFromArray(ArrayList<Double> arrayList) {
        for (Iterator<Double> iterator = arrayList.iterator(); iterator.hasNext();) {
            final Double aDouble = iterator.next();
            if (aDouble >= 99900) {
                // Remove the current element from the iterator and the list.
                iterator.remove();
            }
        }
//        System.out.println("DirectDeleteFromArray\t Now size of array is\t" + arrayList.size());
        return null;
    }

    public Void createNewArrayWithoutElement(ArrayList<Double> arrayList) {
        Object[] objects = arrayList.stream().filter(aDouble -> aDouble < 99900).toArray();
//        System.out.println("CreateNewArray\tNow size of array is\t" + objects.length);
        return null;
    }

    public static <R> long executeVoidFunctionWithTimer(Callable<R> f) throws Exception {
        final Stopwatch timer = Stopwatch.createUnstarted();
        timer.start();
        R r = f.call();
        timer.stop();
        return timer.elapsed(TimeUnit.MICROSECONDS);
    }

}