The technical principles of the JAKARTA Messaging API framework in the Java class library (Analysis of the Technical Principles of Jakarta Messaging in Java Class Libraries)
Analysis of the technical principles of Jakarta Messaging API framework in the Java class library
The Jakarta Messaging API framework in the Java class library provides important tools and functions for message transmission in a distributed system.This framework adopts a series of technical principles that allow developers to easily achieve the goals such as asynchronous communication, decoupling and scalability.In this article, we will analyze the key technical principles of the Jakarta Messaging API framework and provide some Java code examples to help readers better understand.
1. Java Messaging Service (JMS)
The Jakarta Messaging API framework in the Java class library is based on the Java Messaging Service (JMS) specification.JMS is an API used in a distributed system to pass asynchronous messages. It defines the format of the message, the communication mechanism of the producer and the consumer, and the route and transmission of how to perform the message.By implementing the JMS specification, the Jakarta Messaging API framework provides standard interfaces and protocols using message transmission in Java applications.
Below is a simple JMS example, showing how to send and receive messages how to use the Jakarta Messaging API framework:
import javax.jms.*;
public class JmsExample {
public static void main(String[] args) {
try {
// Create a connection factory
ConnectionFactory connectionFactory = new ActiveMQConnectionFactory("tcp://localhost:61616");
// Create a connection
Connection connection = connectionFactory.createConnection();
connection.start();
// Create the meeting
Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the target queue
Destination destination = session.createQueue("myQueue");
// Create message Consumers
MessageConsumer consumer = session.createConsumer(destination);
// Register message monitor
consumer.setMessageListener(message -> {
if (message instanceof TextMessage) {
try {
System.out.println("Received message: " + ((TextMessage) message).getText());
} catch (JMSException e) {
e.printStackTrace();
}
}
});
// Create message producers
MessageProducer producer = session.createProducer(destination);
// Create messages
TextMessage message = session.createTextMessage("Hello, Jakarta Messaging API!");
// Send a message
producer.send(message);
// Turn off the connection
producer.close();
consumer.close();
session.close();
connection.close();
} catch (JMSException e) {
e.printStackTrace();
}
}
}
In this example, we used ActiveMQ as a message agent to create a target queue (called "Myqueue").By creating message producers and consumers, we can send and receive messages between the two.A message monitor is registered among consumers to process the received messages asynchronously.
2. Message agent and message transmission model
Another core technical principle of the Jakarta Messaging API framework is message agency and message transmission model.The message agent is a middleware that is responsible for receiving the message sent by the sender and the route to one or more consumers.By decoupling the sender and the receiver, the message agent provides a flexible and scalable way to transmit messages.
In the Jakarta Messaging API framework, the message transmission model is usually based on two basic modes: Point-to-Point models and PUBLISH/Subscripe models.In point -to -point models, only one consumer can receive each message, and in the release/subscription model, each message can be received by multiple subscribers at the same time.
Below is an example of the release/subscription model:
import javax.jms.*;
public class PubSubExample {
public static void main(String[] args) {
try {
// Create a connection factory
ConnectionFactory connectionFactory = new ActiveMQConnectionFactory("tcp://localhost:61616");
// Create a connection
Connection connection = connectionFactory.createConnection();
connection.start();
// Create the meeting
Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the topic
Topic topic = session.createTopic("myTopic");
// Create subscriber 1
MessageConsumer subscriber1 = session.createConsumer(topic);
subscriber1.setMessageListener(message -> {
if (message instanceof TextMessage) {
try {
System.out.println("Subscriber 1 received message: " + ((TextMessage) message).getText());
} catch (JMSException e) {
e.printStackTrace();
}
}
});
// Create subscriber 2
MessageConsumer subscriber2 = session.createConsumer(topic);
subscriber2.setMessageListener(message -> {
if (message instanceof TextMessage) {
try {
System.out.println("Subscriber 2 received message: " + ((TextMessage) message).getText());
} catch (JMSException e) {
e.printStackTrace();
}
}
});
// Create message producers
MessageProducer producer = session.createProducer(topic);
// Create messages
TextMessage message = session.createTextMessage("Hello, Jakarta Messaging API!");
// make an announcement
producer.send(message);
// Turn off the connection
producer.close();
subscriber1.close();
subscriber2.close();
session.close();
connection.close();
} catch (JMSException e) {
e.printStackTrace();
}
}
}
In this example, we created a theme (called "MyTopic"), and also created two subscribers to subscribe to the theme.When a message producer sends a message, both subscriber 1 and subscriber 2 will receive the message and processed accordingly.
By using message proxy and different message transmission models, the Jakarta Messaging API framework can provide flexible, scalable and high -performance message transmission mechanisms.
In summary, the Jakarta Messaging API framework in the Java class library has provided a set of powerful tools and functions through technical principles such as message agency and message transmission model through technical principles such as message agency and message transmission model.Demand for message transmission.Developers can flexibly use the framework to build a reliable and scalable application based on their business scenarios and needs.
