Chg: #86 - change time and timeUnit storing method (from Integer to int) in ClockManager

Author: remikey

CHANGELOG.md

@@ -18,6 +18,12 @@ This file lists modifications introduced by each version.
   the `MessageEngine` and all `Node.onClock()`).
   Everything is now properly synchronized.
 
+**Symbol modification in ClockManager**
+
+* `ClockManager.currentTime()` now returns an `int` instead of an `Integer`
+
+  This value could never be `null`. The return value being an object was a remnant of previous versions. 
+  
 [issue: #86]: https://github.com/jbotsim/JBotSim/issues/86
 
 ### New icon in the jbotsim-icons module

lib/jbotsim-core/src/main/java/io/jbotsim/core/ClockManager.java

@@ -38,8 +38,8 @@ public class ClockManager {
     HashMap<ClockListener, Integer> countdown = new HashMap<>();
     Class<? extends Clock> clockModel = null;
     Clock clock = null;
-    Integer time = CLOCK_INITIAL_VALUE;
-    Integer timeUnit = 10; // duration of a round in ms
+    int time = CLOCK_INITIAL_VALUE;
+    int timeUnit = 10; // duration of a round in ms
     int nbPauses = 0;
     private boolean firstRound = true;
 
@@ -157,7 +157,7 @@ public void setTimeUnit(int timeUnit){
      * Returns the current round number.
      * @return the current time.
      */
-    public Integer currentTime() {
+    public int currentTime() {
         return time;
     }