fixed ConcurrentModificationException

parameters.json

@@ -1,8 +1,8 @@
 {
-  "width": 25,
-  "height": 25,
-  "jungleRatio": 0.05,
-  "moveEnergy": 0.00001,
+  "width": 15,
+  "height": 15,
+  "jungleRatio": 0.1,
+  "moveEnergy": 1.0,
   "initialEnergy": 100.0,
   "plantEnergy": 25.0,
   "initialAnimals": 10

src/sample/Main.java

@@ -1,20 +1,7 @@
 package sample;
 
 import javafx.application.Application;
-import javafx.application.Platform;
-import javafx.concurrent.Task;
-import javafx.geometry.Insets;
-import javafx.scene.Group;
-import javafx.scene.Scene;
-import javafx.scene.control.Label;
-import javafx.scene.control.TextArea;
-import javafx.scene.paint.Color;
-import javafx.scene.paint.Paint;
-import javafx.scene.text.Text;
 import javafx.stage.Stage;
-import simulation.Simulation;
-import simulation.SimulationErrorException;
-import simulation.StatsWatcher;
 
 public class Main extends Application {
 

src/sample/ParametersLoader.java

@@ -1,14 +1,12 @@
 package sample;
 
-import org.json.simple.JSONArray;
 import org.json.simple.JSONObject;
 import org.json.simple.parser.JSONParser;
 import org.json.simple.parser.ParseException;
 import simulation.InvalidStartingParametersException;
 import simulation.Simulation;
 
 import java.io.IOException;
-import java.io.StringReader;
 import java.nio.file.Files;
 import java.nio.file.Path;
 

src/sample/SimulationThread.java

@@ -9,53 +9,65 @@
 import javafx.scene.paint.Color;
 import javafx.stage.Stage;
 import simulation.Simulation;
+import simulation.SimulationErrorException;
 import simulation.StatsWatcher;
 
+import java.util.concurrent.atomic.AtomicBoolean;
+
 public class SimulationThread extends Thread{
     private final Stage stage = new Stage();
     private final Simulation simulation;
+    private final Scene simulationScene;
+    private final Group root = new Group();
+    private final StatsWatcher statsWatcher;
+    private final SimulationCanvas canvas;
+    private final Label statsLabel = new Label();
+    private final AtomicBoolean paused = new AtomicBoolean(false);
+
     public void run() {
         Platform.runLater(this::displaySimulation);
     }
     public SimulationThread(Simulation simulation){
         this.simulation = simulation;
+        this.simulationScene = new Scene(root, simulation.getWidth()*10+400, Math.max(simulation.getHeight()*10,400), Color.BLACK);
+        this.statsWatcher = new StatsWatcher(simulation);
+        this.canvas = new SimulationCanvas(simulation);
     }
     public void displaySimulation() {
-        final Group root = new Group();
-        final double width = simulation.getWidth()*10+400;
-        final double height = Math.max(simulation.getHeight()*10,400);
-        final Scene simulationScene = new Scene(root, width, height, Color.BLACK);
-
-        final StatsWatcher statsWatcher = new StatsWatcher(simulation);
-        final SimulationCanvas canvas = new SimulationCanvas(simulation);
         canvas.setLayoutX(400);
-        final Label statsLabel = new Label();
         statsLabel.setTextFill(Color.web("#FFFFFF"));
         statsLabel.setPadding(new Insets(5.0));
 
         root.getChildren().add(statsLabel);
         root.getChildren().add(canvas);
         stage.setScene(simulationScene);
+        stage.setTitle("Evolution Simulator");
         stage.setResizable(false);
 
         simulation.start();
         canvas.drawBackground();
         canvas.update();
         stage.show();
+        SimulationThread simulationThread = this;
         Task<Integer> task = new Task<>() {
             @Override protected Integer call() throws Exception {
                 int iterations;
                 for (iterations = 0; true; iterations++) {
                     if (isCancelled()) {
                         break;
                     }
-                    simulation.simulateOneDay();
-                    System.out.println("CANVAS UPDATE start");
-
-                    Platform.runLater(canvas::update);
-                    Platform.runLater(()->{statsLabel.setText(statsWatcher.getSummary());});
-
                     Thread.sleep(100);
+                    if(simulationThread.paused.get()){
+                        continue;
+                    }
+
+                    Platform.runLater(()->{
+                        try {
+                            simulation.simulateOneDay();
+                        } catch (SimulationErrorException e) {
+                            e.printStackTrace();
+                        }
+                        canvas.update(); statsLabel.setText(statsWatcher.getSummary());});
                 }
                 return iterations;
             }