Refactor handle (#75)

* Refactor passing messages to handler

* Add RMIMessage skeleton

* Handle RMI message in RMI module

10 files changed, 95 insertions, 60 deletions

diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/Agent.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Agent.java
index 4e75a51..1b078cf 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/Agent.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Agent.java
@@ -5,29 +5,29 @@ import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;
 
-import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
 import pl.edu.mimuw.cloudatlas.agent.modules.Module;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
 import pl.edu.mimuw.cloudatlas.agent.modules.RMI;
 import pl.edu.mimuw.cloudatlas.agent.modules.TimerScheduler;
 
 public class Agent {
 
-    public static HashMap<AgentMessage.AgentModule, Module> initializeModules() {
-        HashMap<AgentMessage.AgentModule, Module> modules = new HashMap<AgentMessage.AgentModule, Module>();
-        modules.put(AgentMessage.AgentModule.TIMER_SCHEDULER, new TimerScheduler(AgentMessage.AgentModule.TIMER_SCHEDULER));
-        modules.put(AgentMessage.AgentModule.RMI, new RMI(AgentMessage.AgentModule.RMI));
+    public static HashMap<ModuleType, Module> initializeModules() {
+        HashMap<ModuleType, Module> modules = new HashMap<ModuleType, Module>();
+        modules.put(ModuleType.TIMER_SCHEDULER, new TimerScheduler(ModuleType.TIMER_SCHEDULER));
+        modules.put(ModuleType.RMI, new RMI(ModuleType.RMI));
         // TODO add modules as we implement them
         return modules;
     }
 
-    public static HashMap<AgentMessage.AgentModule, Executor> initializeExecutors(
-            HashMap<AgentMessage.AgentModule, Module> modules) {
-        HashMap<AgentMessage.AgentModule, Executor> executors = new HashMap<AgentMessage.AgentModule, Executor>();
+    public static HashMap<ModuleType, Executor> initializeExecutors(
+            HashMap<ModuleType, Module> modules) {
+        HashMap<ModuleType, Executor> executors = new HashMap<ModuleType, Executor>();
         Iterator it = modules.entrySet().iterator();
 
         while (it.hasNext()) {
-            Map.Entry<AgentMessage.AgentModule, Module> moduleEntry =
-                    (Map.Entry<AgentMessage.AgentModule, Module>) it.next();
+            Map.Entry<ModuleType, Module> moduleEntry =
+                    (Map.Entry<ModuleType, Module>) it.next();
             Module module = moduleEntry.getValue();
             Executor executor = new Executor(module);
             executors.put(moduleEntry.getKey(), executor);
@@ -36,13 +36,13 @@ public class Agent {
         return executors;
     }
 
-    public static ArrayList<Thread>  initializeExecutorThreads(HashMap<AgentMessage.AgentModule, Executor> executors) {
+    public static ArrayList<Thread>  initializeExecutorThreads(HashMap<ModuleType, Executor> executors) {
         ArrayList<Thread> executorThreads = new ArrayList<Thread>();
         Iterator it = executors.entrySet().iterator();
 
         while (it.hasNext()) {
-            Map.Entry<AgentMessage.AgentModule, Executor> executorEntry =
-                    (Map.Entry<AgentMessage.AgentModule, Executor>) it.next();
+            Map.Entry<ModuleType, Executor> executorEntry =
+                    (Map.Entry<ModuleType, Executor>) it.next();
             Thread thread = new Thread(executorEntry.getValue());
             thread.setDaemon(true);
             System.out.println("Initializing executor " + executorEntry.getKey());
@@ -60,8 +60,8 @@ public class Agent {
     }
 
     public static void runModulesAsThreads() {
-        HashMap<AgentMessage.AgentModule, Module> modules = initializeModules();
-        HashMap<AgentMessage.AgentModule, Executor> executors = initializeExecutors(modules);
+        HashMap<ModuleType, Module> modules = initializeModules();
+        HashMap<ModuleType, Executor> executors = initializeExecutors(modules);
         ArrayList<Thread> executorThreads = initializeExecutorThreads(executors);
 
         Thread eventBusThread = new Thread(new EventBus(executors));
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java
index 37c125a..4f939b6 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java
@@ -1,6 +1,7 @@
 package pl.edu.mimuw.cloudatlas.agent;
 
 import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
 
 import java.util.HashMap;
 import java.util.Iterator;
@@ -12,18 +13,18 @@ import java.util.concurrent.LinkedBlockingQueue;
  */
 public class EventBus implements Runnable {
     private LinkedBlockingQueue<AgentMessage> events;
-    private HashMap<AgentMessage.AgentModule, Executor> executors;
+    private HashMap<ModuleType, Executor> executors;
 
     void setEventBusReference() {
         Iterator it = this.executors.entrySet().iterator();
         while (it.hasNext()) {
-            Map.Entry<AgentMessage.AgentModule, Executor> executorEntry =
-                    (Map.Entry<AgentMessage.AgentModule, Executor>) it.next();
+            Map.Entry<ModuleType, Executor> executorEntry =
+                    (Map.Entry<ModuleType, Executor>) it.next();
             executorEntry.getValue().setEventBus(this);
         }
     }
 
-    EventBus(HashMap<AgentMessage.AgentModule, Executor> executors) {
+    EventBus(HashMap<ModuleType, Executor> executors) {
         this.executors = executors;
         setEventBusReference();
         this.events = new LinkedBlockingQueue<AgentMessage>();
@@ -43,13 +44,11 @@ public class EventBus implements Runnable {
     }
 
     public void routeMessage(AgentMessage msg) throws InterruptedException {
-        assert msg.getCorrectMessageType() == msg.getDestinationModule();
         System.out.println("Event bus routing message");
         executors.get(msg.getDestinationModule()).addMessage(msg);
     }
 
     public void addMessage(AgentMessage msg) throws InterruptedException {
-        assert msg.getCorrectMessageType() == msg.getDestinationModule();
         this.events.put(msg);
     }
 }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java
index 6ebf6a6..d648fac 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java
@@ -30,6 +30,10 @@ public class Executor implements Runnable {
             } catch (InterruptedException e) {
                 System.out.println("Executor interrupted. Exiting loop.");
                 break;
+            } catch (Module.InvalidMessageType e) {
+                System.out.println("Executor got a message with type it can't handle");
+                System.out.println(e);
+                break;
             }
         }
     }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/AgentMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/AgentMessage.java
index b71831f..f343e0f 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/AgentMessage.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/AgentMessage.java
@@ -1,36 +1,25 @@
 package pl.edu.mimuw.cloudatlas.agent.messages;
 
-public abstract class AgentMessage {
-
-    public enum AgentModule {
-        TIMER_SCHEDULER,
-        TIMER_GTP,
-        RMI,
-        UDP,
-        GOSSIP_IN,
-        GOSSIP_OUT,
-        STATE,
-        QUERY
-    }
+import pl.edu.mimuw.cloudatlas.agent.modules.Module;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
 
+public abstract class AgentMessage {
     private String messageId;
-    private AgentModule destinationModule;
+    private ModuleType destinationModule;
     private long timestamp;
 
-    public AgentMessage(String messageId, AgentModule destinationModule, long timestamp) {
+    public AgentMessage(String messageId, ModuleType destinationModule, long timestamp) {
         this.messageId = messageId;
         this.destinationModule = destinationModule;
         this.timestamp = timestamp;
     }
 
-    public AgentMessage(String messageId, AgentModule destinationModule) {
+    public AgentMessage(String messageId, ModuleType destinationModule) {
         this.messageId = messageId;
         this.destinationModule = destinationModule;
         this.timestamp = System.currentTimeMillis() / 1000L;
     }
 
-    public abstract AgentModule getCorrectMessageType();
-
     public String getMessageId() {
         return messageId;
     }
@@ -39,14 +28,16 @@ public abstract class AgentMessage {
         this.messageId = messageId;
     }
 
-    public AgentModule getDestinationModule() {
+    public ModuleType getDestinationModule() {
         return destinationModule;
     }
 
-    public void setDestinationModule(AgentModule destinationModule) {
+    public void setDestinationModule(ModuleType destinationModule) {
         this.destinationModule = destinationModule;
     }
 
+    public abstract void callMe(Module module) throws InterruptedException, Module.InvalidMessageType;
+
     public long getTimestamp() {
         return timestamp;
     }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/RMIMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/RMIMessage.java
new file mode 100644
index 0000000..a8e3afb
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/RMIMessage.java
@@ -0,0 +1,14 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import pl.edu.mimuw.cloudatlas.agent.modules.Module;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
+
+public class RMIMessage extends AgentMessage {
+    public RMIMessage(String messageId, long timestamp) {
+        super(messageId, ModuleType.RMI, timestamp);
+    }
+
+    public void callMe(Module module) throws InterruptedException, Module.InvalidMessageType {
+        module.handleTyped(this);
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/TimerSchedulerMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/TimerSchedulerMessage.java
index 333b381..8566d67 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/TimerSchedulerMessage.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/TimerSchedulerMessage.java
@@ -1,6 +1,8 @@
 package pl.edu.mimuw.cloudatlas.agent.messages;
 
 import pl.edu.mimuw.cloudatlas.agent.modules.TimerScheduledTask;
+import pl.edu.mimuw.cloudatlas.agent.modules.Module;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
 
 public class TimerSchedulerMessage extends AgentMessage {
     private String requestId;
@@ -9,13 +11,12 @@ public class TimerSchedulerMessage extends AgentMessage {
     private TimerScheduledTask task;
 
     public TimerSchedulerMessage(String messageId,
-                                 AgentModule destinationModule,
                                  long timestamp,
                                  String requestId,
                                  long delay,
                                  long baseTime,
                                  TimerScheduledTask task) {
-        super(messageId, destinationModule, timestamp);
+        super(messageId, ModuleType.TIMER_SCHEDULER, timestamp);
         this.requestId = requestId;
         this.delay = delay;
         this.baseTime = baseTime;
@@ -48,10 +49,9 @@ public class TimerSchedulerMessage extends AgentMessage {
 
     public String getRequestId() { return requestId; }
 
-    public void setRequestId(String requestId) { this.requestId = requestId; }
-
-    @Override
-    public AgentModule getCorrectMessageType() {
-        return AgentModule.TIMER_SCHEDULER;
+    public void callMe(Module module) throws InterruptedException, Module.InvalidMessageType {
+        module.handleTyped(this);
     }
+
+    public void setRequestId(String requestId) { this.requestId = requestId; }
 }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java
index 9744971..a50a95f 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java
@@ -2,19 +2,37 @@ package pl.edu.mimuw.cloudatlas.agent.modules;
 
 import pl.edu.mimuw.cloudatlas.agent.Executor;
 import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.TimerSchedulerMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.RMIMessage;
 
 /*
  * A Module is a (potentially stateful) event handler.
  */
 public abstract class Module {
-    protected AgentMessage.AgentModule moduleType;
+    public class InvalidMessageType extends Exception {
+        public InvalidMessageType(String message) {
+            super(message);
+        }
+    }
+
+    protected ModuleType moduleType;
     protected Executor executor;
 
-    public Module(AgentMessage.AgentModule moduleType) {
+    public Module(ModuleType moduleType) {
         this.moduleType = moduleType;
     }
 
-    public abstract void handle(AgentMessage event) throws InterruptedException ;
+    public void handle(AgentMessage event) throws InterruptedException, InvalidMessageType {
+        event.callMe(this);
+    }
+
+    public void handleTyped(TimerSchedulerMessage message) throws InterruptedException, InvalidMessageType {
+        throw new InvalidMessageType("Got a TimerSchedulerMessage in module " + moduleType.toString());
+    }
+
+    public void handleTyped(RMIMessage message) throws InterruptedException, InvalidMessageType {
+        throw new InvalidMessageType("Got an RMIMessage in module " + moduleType.toString());
+    }
 
     public void setExecutor(Executor executor) {
         this.executor = executor;
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java
new file mode 100644
index 0000000..ff4a92e
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java
@@ -0,0 +1,12 @@
+package pl.edu.mimuw.cloudatlas.agent.modules;
+
+public enum ModuleType {
+    TIMER_SCHEDULER,
+    TIMER_GTP,
+    RMI,
+    UDP,
+    GOSSIP_IN,
+    GOSSIP_OUT,
+    STATE,
+    QUERY
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/RMI.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/RMI.java
index 452b214..1a86fc7 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/RMI.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/RMI.java
@@ -2,7 +2,7 @@ package pl.edu.mimuw.cloudatlas.agent.modules;
 
 import pl.edu.mimuw.cloudatlas.agent.ApiImplementation;
 import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
-import pl.edu.mimuw.cloudatlas.agent.messages.TimerSchedulerMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.RMIMessage;
 import pl.edu.mimuw.cloudatlas.api.Api;
 import pl.edu.mimuw.cloudatlas.interpreter.Main;
 import pl.edu.mimuw.cloudatlas.model.ZMI;
@@ -12,7 +12,7 @@ import java.rmi.registry.Registry;
 import java.rmi.server.UnicastRemoteObject;
 
 public class RMI extends Module {
-    public RMI(AgentMessage.AgentModule moduleType) {
+    public RMI(ModuleType moduleType) {
         super(moduleType);
         runRegistry();
     }
@@ -32,8 +32,6 @@ public class RMI extends Module {
         }
     }
 
-    @Override
-    public void handle(AgentMessage event) throws InterruptedException {
-        assert event.getDestinationModule() == event.getCorrectMessageType();
+    public void handleTyped(RMIMessage event) throws InterruptedException {
     }
 }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/TimerScheduler.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/TimerScheduler.java
index 9390940..68a9326 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/TimerScheduler.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/TimerScheduler.java
@@ -2,6 +2,7 @@ package pl.edu.mimuw.cloudatlas.agent.modules;
 
 import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
 import pl.edu.mimuw.cloudatlas.agent.messages.TimerSchedulerMessage;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
 
 import java.util.Timer;
 
@@ -17,17 +18,15 @@ import java.util.Timer;
 public class TimerScheduler extends Module {
     private Timer timer;
 
-    public TimerScheduler(AgentMessage.AgentModule moduleType) {
+    public TimerScheduler(ModuleType moduleType) {
         super(moduleType);
-        assert moduleType == AgentMessage.AgentModule.TIMER_SCHEDULER;
+        assert moduleType == ModuleType.TIMER_SCHEDULER;
         this.timer = new Timer();
         System.out.println("TimerScheduler instance initialized");
     }
 
     @Override
-    public void handle(AgentMessage event) throws InterruptedException {
-        assert event.getDestinationModule() == event.getCorrectMessageType();
-        TimerSchedulerMessage timerEvent = (TimerSchedulerMessage) event;
+    public void handleTyped(TimerSchedulerMessage timerEvent) throws InterruptedException {
         addTask(timerEvent);
     }