Implement executor (#65)

3 files changed, 52 insertions, 0 deletions

diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java
new file mode 100644
index 0000000..47cb1ff
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/EventBus.java
@@ -0,0 +1,7 @@
+package pl.edu.mimuw.cloudatlas.agent;
+
+/*
+ * The EventBus routes messages sent between Modules.
+ */
+public class EventBus {
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java
new file mode 100644
index 0000000..0651a9b
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Executor.java
@@ -0,0 +1,35 @@
+package pl.edu.mimuw.cloudatlas.agent;
+
+import java.util.concurrent.LinkedBlockingQueue;
+
+import pl.edu.mimuw.cloudatlas.agent.message.AgentMessage;
+
+/*
+ * Queues messages sent to a particular module and ensures they are eventually
+ * handled.
+ */
+public class Executor implements Runnable {
+    private Module module;
+    private LinkedBlockingQueue<AgentMessage> events;
+
+    public Executor(Module module) {
+        this.module = module;
+        this.events = new LinkedBlockingQueue<AgentMessage>();
+    }
+
+    public void run() {
+        while (!Thread.currentThread().interrupted()) {
+            try {
+                AgentMessage event = events.take();
+                module.handle(event);
+            } catch (InterruptedException e) {
+                System.out.println("Executor interrupted. Exiting loop.");
+                break;
+            }
+        }
+    }
+
+    public void addMessage(AgentMessage event) throws InterruptedException {
+        events.put(event);
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/Module.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Module.java
new file mode 100644
index 0000000..46df31b
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/Module.java
@@ -0,0 +1,10 @@
+package pl.edu.mimuw.cloudatlas.agent;
+
+import pl.edu.mimuw.cloudatlas.agent.message.AgentMessage;
+
+/*
+ * A Module is a (potentially stateful) event handler.
+ */
+public abstract class Module {
+    public abstract void handle(AgentMessage event);
+}