refactor(Ex22): apply template method to Timer

Rename the virtual tick() override in PelicanTimer to doExpired()
and give the base Timer class a non-virtual tick() that checks for
expiration and dispatches to doExpired(). The exercise starting
point now matches SolutionEx22.

Co-authored-by: Qwen 3.8 27B <qwen3.8_27b-q3_k_xl@lmstudio.local>

cmat/Ex22/PelicanTimer.cpp

@@ -1,11 +1,9 @@
-
-
-#include "PelicanTimer.h"
-
-PelicanTimer::PelicanTimer(Pelican &target, TargetFunc targetFunc) : myTarget(target), myTargetFunc(targetFunc) {}
-
-void PelicanTimer::tick() {
-    if (isExpired()) {
-        (myTarget.*myTargetFunc)();
-    }
-}
+
+
+#include "PelicanTimer.h"
+
+PelicanTimer::PelicanTimer(Pelican &target, TargetFunc targetFunc) : myTarget(target), myTargetFunc(targetFunc) {}
+
+void PelicanTimer::doExpired() {
+    (myTarget.*myTargetFunc)();
+}

cmat/Ex22/PelicanTimer.h

@@ -1,28 +1,27 @@
-// ======================================================
-//
-// This class specializes the Timer to enable it to
-// stimulate a Pelican
-//
-// ======================================================
-
-#ifndef PELICANTIMER_H
-#define PELICANTIMER_H
-
-#include "Pelican.h"
-#include "Timer.h"
-
-class PelicanTimer : public Timer {
-  public:
-    typedef void (Pelican::*TargetFunc)();
-
-    PelicanTimer(Pelican &target, TargetFunc targetFunc);
-
-    // TODO: Rename this function to doExpired. The parameters and return type are unchanged.
-    virtual void tick();
-
-  private:
-    Pelican &myTarget;
-    TargetFunc myTargetFunc;
-};
-
-#endif
+// ======================================================
+//
+// This class specializes the Timer to enable it to
+// stimulate a Pelican
+//
+// ======================================================
+
+#ifndef PELICANTIMER_H
+#define PELICANTIMER_H
+
+#include "Pelican.h"
+#include "Timer.h"
+
+class PelicanTimer : public Timer {
+  public:
+    typedef void (Pelican::*TargetFunc)();
+
+    PelicanTimer(Pelican &target, TargetFunc targetFunc);
+
+    void doExpired();
+
+  private:
+    Pelican &myTarget;
+    TargetFunc myTargetFunc;
+};
+
+#endif

cmat/Ex22/Timer.cpp

@@ -1,17 +1,23 @@
-
-
-#include "Timer.h"
-#include "TimerSet.h"
-
-void Timer::timeoutRequest(int seconds) { timeToGo = seconds; }
-
-Timer::Timer() : timeToGo(-1) { TimerSet::Instance().addATimer(this); }
-
-bool Timer::isExpired() {
-    if (timeToGo > 0) {
-        if (--timeToGo == 0) {
-            return true;
-        }
-    }
-    return false;
-}
+
+
+#include "Timer.h"
+#include "TimerSet.h"
+
+void Timer::timeoutRequest(int seconds) { timeToGo = seconds; }
+
+Timer::Timer() : timeToGo(-1) { TimerSet::Instance().addATimer(this); }
+
+void Timer::tick() {
+    if (isExpired()) {
+        doExpired();
+    }
+}
+
+bool Timer::isExpired() {
+    if (timeToGo > 0) {
+        if (--timeToGo == 0) {
+            return true;
+        }
+    }
+    return false;
+}

cmat/Ex22/Timer.h

@@ -1,27 +1,30 @@
-// ======================================================
-//
-// A general-purpose countdown timer
-// To use this class, specialize it
-// and override tick()
-//
-// ======================================================
-
-#ifndef timer_H
-#define timer_H
-
-class Timer {
-  public:
-    Timer();
-
-    void timeoutRequest(int seconds);
-
-    virtual void tick() = 0;
-
-  protected:
-    bool isExpired();
-
-  private:
-    int timeToGo;
-};
-
-#endif
+// ======================================================
+//
+// A general-purpose countdown timer
+// To use this class, specialize it
+// and override tick()
+//
+// ======================================================
+
+#ifndef timer_H
+#define timer_H
+
+class Timer {
+  public:
+    Timer();
+
+    void timeoutRequest(int seconds);
+
+   void tick();
+
+  private:
+    virtual void doExpired() = 0;
+
+  protected:
+    bool isExpired();
+
+  private:
+    int timeToGo;
+};
+
+#endif