From fbd07659c788f1727b281385283a733daa7c858f Mon Sep 17 00:00:00 2001
From: Lumijiez <danthevip@gmail.com>
Date: Fri, 22 Nov 2024 20:14:20 +0200
Subject: [PATCH] Producer doesn't busy-wait now

---
 .../main/java/io/github/lumijiez/Main.java    | 95 +++++++++----------
 1 file changed, 45 insertions(+), 50 deletions(-)

diff --git a/SymphonyProducer/src/main/java/io/github/lumijiez/Main.java b/SymphonyProducer/src/main/java/io/github/lumijiez/Main.java
index eecb332..a7f564a 100644
--- a/SymphonyProducer/src/main/java/io/github/lumijiez/Main.java
+++ b/SymphonyProducer/src/main/java/io/github/lumijiez/Main.java
@@ -2,16 +2,17 @@ package io.github.lumijiez;
 
 import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
-import com.rabbitmq.client.ConnectionFactory;
-import com.rabbitmq.client.Connection;
 import com.rabbitmq.client.Channel;
+import com.rabbitmq.client.Connection;
+import com.rabbitmq.client.ConnectionFactory;
 
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.Random;
-import java.util.Timer;
-import java.util.TimerTask;
-import java.util.concurrent.TimeoutException;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.CountDownLatch;
 
 public class Main {
     private static final String QUEUE_NAME = "random_json_queue";
@@ -20,59 +21,53 @@ public class Main {
     private static final String RABBITMQ_PASSWORD = "symphony";
 
     public static void main(String[] args) {
+        CountDownLatch latch = new CountDownLatch(1);
+
+        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+            System.out.println("Shutdown signal received.");
+            latch.countDown();
+        }));
+
+        boolean success = connectToRabbitMQ(latch);
+    }
+
+    private static boolean connectToRabbitMQ(CountDownLatch latch) {
         ConnectionFactory factory = new ConnectionFactory();
         factory.setHost(RABBITMQ_HOST);
         factory.setUsername(RABBITMQ_USER);
         factory.setPassword(RABBITMQ_PASSWORD);
 
-        Connection connection = null;
-        Channel channel = null;
+        try (Connection connection = factory.newConnection();
+             Channel channel = connection.createChannel();
+             ScheduledExecutorService scheduler = Executors.newSingleThreadScheduledExecutor()) {
 
-        while (true) {
+            channel.queueDeclare(QUEUE_NAME, false, false, false, null);
+            System.out.println("Connected to RabbitMQ and queue declared.");
+
+            scheduler.scheduleAtFixedRate(() -> {
+                try {
+                    String jsonMessage = generateRandomJson();
+                    channel.basicPublish("", QUEUE_NAME, null, jsonMessage.getBytes(StandardCharsets.UTF_8));
+                    System.out.println("Sent: " + jsonMessage);
+                } catch (IOException e) {
+                    System.err.println("Failed to send message: " + e.getMessage());
+                }
+            }, 0, 10, TimeUnit.SECONDS);
+
+            latch.await();
+            scheduler.shutdown();
+
+            return scheduler.awaitTermination(5, TimeUnit.SECONDS);
+        } catch (Exception e) {
+            System.err.println("RabbitMQ connection error: " + e.getMessage());
             try {
-                System.out.println("Attempting to connect to RabbitMQ...");
-
-                connection = factory.newConnection();
-                channel = connection.createChannel();
-
-                channel.queueDeclare(QUEUE_NAME, false, false, false, null);
-                System.out.println("Connected to RabbitMQ and queue declared.");
-
-                Timer timer = new Timer(true);
-                Channel finalChannel = channel;
-                timer.scheduleAtFixedRate(new TimerTask() {
-                    @Override
-                    public void run() {
-                        try {
-                            String jsonMessage = generateRandomJson();
-                            finalChannel.basicPublish("", QUEUE_NAME, null, jsonMessage.getBytes(StandardCharsets.UTF_8));
-                            System.out.println("Sent: " + jsonMessage);
-                        } catch (IOException e) {
-                            System.err.println("Failed to send message: " + e.getMessage());
-                        }
-                    }
-                }, 0, 10000);
-
-                System.out.println("Press Ctrl+C to exit.");
-                Thread.sleep(Long.MAX_VALUE);
-                break;
-
-            } catch (IOException | TimeoutException | InterruptedException e) {
-                System.err.println("Failed to connect to RabbitMQ: " + e.getMessage());
-                System.err.println("Retrying in 5 seconds...");
-                try {
-                    if (connection != null && connection.isOpen()) connection.close();
-                    if (channel != null && channel.isOpen()) channel.close();
-                } catch (IOException | TimeoutException ignored) {
-                }
-
-                try {
-                    Thread.sleep(5000);
-                } catch (InterruptedException ie) {
-                    Thread.currentThread().interrupt();
-                }
+                Thread.sleep(5000);
+                connectToRabbitMQ(latch);
+            } catch (InterruptedException ie) {
+                Thread.currentThread().interrupt();
             }
         }
+        return false;
     }
 
     private static String generateRandomJson() {
@@ -84,4 +79,4 @@ public class Main {
 
         return jsonObject.toString();
     }
-}
+}
\ No newline at end of file