Java Messaging Service (JMS) Topic Connection 🗨️

Purpose: Demonstrate a simple JMS Topic-based publish/subscribe application using GlassFish/Payara’s JMS provider. Includes publisher (JMS-First-Client), subscriber (JMS-Second-Client), server configuration screenshots, and Admin Console startup instructions.

---

📁 Project Structure

Java-Messaging-Service/
├─ JMS-First-Client/                # Publisher application (Maven project)
├─ JMS-Second-Client/               # Subscriber application (Maven project)
├─ How to excute admin console commands.txt  # Admin Console start/stop guide
├─ JMS Connection Factory.PNG       # Screenshot: JMS Connection Factory in Admin Console
├─ JMS Destination Resources.PNG    # Screenshot: JMS Topic resources
├─ JMS-First-Client Output.PNG      # Screenshot: Publisher console output
└─ JMS-Second-Client Output.PNG     # Screenshot: Subscriber console output

---

🛠 Prerequisites

• Java 11+ JDK
• Apache Maven 3.6+
• GlassFish 7 or Payara 6 (Java EE /Jakarta EE compatible)
• Ability to run asadmin CLI or use the Admin Console

---

1. Configure JMS Resources in Server

1.1 Start GlassFish Domain

Refer to the Admin Console section below for exact commands to start/stop your server.

1.2 Create a JMS Connection Factory

1. Open GlassFish Admin Console at http://localhost:4848.

2. Navigate to Resources ▶ JMS ▶ Connection Factories ▶ New.

3. Enter:

   • JNDI Name: jms/MyConnectionFactory
   • Resource Type: javax.jms.TopicConnectionFactory

4. Click Save.

Alternatively via CLI:

asadmin create-jms-resource \
  --restype javax.jms.TopicConnectionFactory \
  --property Name=MyConnectionFactory jms/MyConnectionFactory

1.3 Create a JMS Topic Destination

1. In Admin Console, go to Resources ▶ JMS ▶ Destination Resources ▶ New.

2. Set:

   • JNDI Name: jms/MyTopic
   • Type: javax.jms.Topic
   • Physical Destination Name: MyTopic

3. Click Save.

Alternatively via CLI:

asadmin create-jms-resource \
  --restype javax.jms.Topic \
  --property Name=MyTopic jms/MyTopic

---

2. Publisher: JMS-First-Client

2.1 Build

cd JMS-First-Client
mvn clean package

2.2 Run

java -jar target/JMS-First-Client-1.0.jar

• Type any text and press Enter to publish a message to the topic.
• Type exit to terminate the application.


Key Code Snippet

InitialContext ctx = new InitialContext();
TopicConnectionFactory factory = (TopicConnectionFactory)
    ctx.lookup("jms/MyConnectionFactory");
TopicConnection conn = factory.createTopicConnection();
conn.start();
TopicSession session = conn.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
Topic topic = (Topic) ctx.lookup("jms/MyTopic");
TopicPublisher publisher = session.createPublisher(topic);
Scanner scanner = new Scanner(System.in);

while (true) {
    String text = scanner.nextLine();
    if ("exit".equalsIgnoreCase(text)) break;
    TextMessage msg = session.createTextMessage(text);
    publisher.publish(msg);
}

---

3. Subscriber: JMS-Second-Client

3.1 Build

cd JMS-Second-Client
mvn clean package

3.2 Run

java -jar target/JMS-Second-Client-1.0.jar

• The subscriber listens indefinitely and prints messages as they arrive.


Key Code Snippet

InitialContext ctx = new InitialContext();
TopicConnectionFactory factory = (TopicConnectionFactory)
    ctx.lookup("jms/MyConnectionFactory");
TopicConnection conn = factory.createTopicConnection();
conn.start();
TopicSession session = conn.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
Topic topic = (Topic) ctx.lookup("jms/MyTopic");
TopicSubscriber subscriber = session.createSubscriber(topic);

subscriber.setMessageListener(message -> {
    try {
        String text = message.getBody(String.class);
        System.out.println("Received: " + text);
    } catch (JMSException e) {
        e.printStackTrace();
    }
});

// Keep application alive
Thread.currentThread().join();

---

4. Admin Console Commands

# How to start Admin Console
PS> cd "C:\Program Files\glassfish7\bin"
PS> .\asadmin start-domain domain1
Waiting for domain1 to start ......
Successfully started domain1 (Admin Port: 4848)

# How to stop Admin Console
PS> .\asadmin stop-domain domain1

# Watch Real-Time Server Log
PS> Get-Content \
       "C:\Program Files\glassfish7\glassfish\domains\domain1\logs\server.log" -Wait

(Adapt paths if using Payara: C:\Program Files\payara6\bin)

---

📖 Summary & Next Steps

• You now have a fully functional JMS pub/sub example.
• Consider extending to a Queue model, durable subscribers, or JMS Transactions.
• Integrate with a Jakarta EE web app to push/receive messages from HTTP endpoints.

Enjoy messaging with JMS!