Feedback

src/main/java/EventListener.java

@@ -1,4 +1,4 @@
-public class EventListener {
+public class EventListener extends Thread{
 
     private String messageToListenFor;
     private String messageToReplyWith;
@@ -17,16 +17,24 @@ public EventListener(String message, String reply, Tracker tracker) {
     }
 
     public void run() {
+        while (!readyToQuit()) {
+            if (shouldReply()) {
+                reply();
+            }
+        }
     }
 
     public Boolean readyToQuit() {
-        return null;
+        return eventTracker.has("quit");
     }
 
     public Boolean shouldReply() {
-        return null;
+        return eventTracker.has(messageToListenFor);
     }
 
     public void reply() {
+        eventTracker.handle(messageToListenFor, () -> {
+            System.out.println(messageToReplyWith);
+        });
     }
 }

src/main/java/EventTracker.java

@@ -12,17 +12,30 @@ private EventTracker() {
     }
 
     synchronized public static EventTracker getInstance() {
-        return null;
+        return INSTANCE;
     }
 
     synchronized public void push(String message) {
+        Integer count = tracker.getOrDefault(message, 0);
+        tracker.put(message, count + 1);
     }
 
     synchronized public Boolean has(String message) {
-        return null;
+        Integer count = tracker.getOrDefault(message, 0);
+        return tracker.containsKey(message) && count > 0;
     }
 
     synchronized public void handle(String message, EventHandler e) {
+        try {
+            e.handle();
+            this.tracker.put(message, this.tracker.get(message) - 1);
+        } catch (NullPointerException n) {
+            System.out.println("Currently untracked.");
+        }
+    }
+
+    public Map<String, Integer> getTracker() {
+        return this.tracker;
     }
 
     // Do not use this. This constructor is for tests only

src/test/java/EventListenerTest.java

@@ -37,7 +37,6 @@ class TrackerMock implements Tracker {
         public boolean itemWasPushed;
         public boolean eventWasHandled;
 
-        @Override
         public Map<String, Integer> tracker() {
             return null;
         }
@@ -48,7 +47,7 @@ public void push(String message) {
         }
 
         @Override
-        public boolean has(String message) {
+        public Boolean has(String message) {
             return true;
         }
 

src/test/java/EventTrackerTest.java

@@ -32,7 +32,7 @@ public void tracker() {
 
         eventTracker.push("test");
 
-        Assert.assertEquals(testList, eventTracker.tracker());
+        Assert.assertEquals(testList, eventTracker.getTracker());
 
     }