procedural-vs-OOP/src/main/java/de/hsfulda/pmuw/oop/CgolBoardOop.java

package de.hsfulda.pmuw.oop;

import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;

public class CgolBoardOop {
  private final Collection<CgolCell> activeCells ;
  private final CellCreator cellCreator;
  private boolean isOptimized;

  CgolBoardOop(CellCreator cellCreator, boolean isOptimized) {
    this.cellCreator = cellCreator;
    this.isOptimized = isOptimized;
    activeCells = isOptimized? new HashSet<>():new ArrayList<>();
  }

  public void initialize() {
    cellCreator.createCells(activeCells, isOptimized);
  }

  public void nextGen() {
    List<CgolCell> currentGeneration = new ArrayList<>(activeCells);
    if (isOptimized)
      activeCells.clear();
    currentGeneration.stream().parallel().forEach(CgolCell::calculateNextGeneration);
    currentGeneration.stream().parallel().forEach(CgolCell::switchState);
  }
  private long countAliveCells() {
    return activeCells.stream().filter(CgolCell::isAlive).count();
  }

  public static void main(String[] args) {
    boolean isOptimized = true;
    startGame(!isOptimized);
    startGame(isOptimized);
  }

  private static void startGame(boolean isOptimized) {
    long start = Calendar.getInstance().getTimeInMillis();
    CgolBoardOop cgolBoard = new CgolBoardOop(new CellCreator(), isOptimized);
    cgolBoard.initialize();
    long end = Calendar.getInstance().getTimeInMillis();
    System.out.println(String.format("initializing took: %sms", end - start));
    start = Calendar.getInstance().getTimeInMillis();
    int iterations = 1000;
    for (int i = 0; i < iterations; i++) {
      cgolBoard.nextGen();
      if (0 == i % (isOptimized? 100:100))
        System.out.println(String.format("iteration %6d cells alife: %7s , cells active %7s",i,cgolBoard.countAliveCells(),cgolBoard.activeCells.size()));
    }
    end = Calendar.getInstance().getTimeInMillis();
    System.out.println(
        String.format("time spend for %d iterations: %sms, optimized: %s\n\n", iterations, end - start, isOptimized));
  }

}