Hi,
I would appreciate some help about unsubscribing a durable subscriber from a topic.
I found many examples on the web but nothing matching with my use case.
Here is my use case :
I've got 3 topics : Topic1, 2 & 3
I've got 3 durable subscribers : User1, 2 & 3
User1 is a durable subscriber for Topics 2 & 3
User2 is a durable subscriber for Topics 1 & 3
User3 is a durable subscriber for Topics 1 & 2
A MessageListener is ON for each subscriber.
To register a subscriber (here : User1), I use :
Receiver receiver1 = new Receiver(user1);
Each user's got its own ClientID (its name).
Then, to subscribe this user to topics (here : topics 2 & 3), I use :
receiver1.receiveMessage(topic2);
receiver1.receiveMessage(topic3);
Each subscription's got its own DurableID.
DurableID is generated like this : ClientID+Topic_Name
Sometimes, a User may want to unsubscribe from one particular topic, but not all of them.
If User1 want to unsubscribe from Topic3, I will do something like this :
session.unsubscribe(DurableID);
with DurableID = User1Topic3
Where I've got a problem is that when I want to unsubscribe, I've got an error message :
"javax.jms.JMSException: Durable consumer is in use"
If I try a "consumer.close()" before, it doesn't work more.
I really don't see how to workaround this problem. User may want to stop a single subscription but not all of the topics he's subscribed.
Moreover, this decision is a user one. I don't see how it could be done without this user to be online.
Here is the code of my Receiver class. It's not clean, but I try everything, adding and deleting lines until it's good.
Thanx for your help.
package com.citizenweb.classes;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.ObjectMessage;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;
import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.ActiveMQSession;
import org.apache.activemq.broker.region.Destination;
import com.citizenweb.interfaces.PostIF;
import com.citizenweb.interfaces.UserIF;
import com.citizenweb.classes.Post;
public class Receiver implements MessageListener, Serializable {
private static final long serialVersionUID = 1L;
private ActiveMQConnectionFactory factory = null;
private ActiveMQConnection connection = null;
private ActiveMQSession session = null;
private Topic destination = null;
private MessageConsumer consumer = null;
UserIF userTopic = new User();
UserIF userSubscriber = new User();
List<Message> listeMsg = new ArrayList<Message>();
public Receiver(UserIF subscriber) {
this.userSubscriber = subscriber;
}
public void connect() {
try {
factory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_BROKER_URL);
// TODO Mécanisme de sécurité d'ActiveMQ à rétablir en production
factory.setTrustAllPackages(true);
connection = (ActiveMQConnection) factory.createConnection();
// ClientID :
// https://qnalist.com/questions/2068823/create-durable-topic-subscriber
connection.setClientID(userSubscriber.toString());
connection.start();
session = (ActiveMQSession) connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
} catch (JMSException e) {
e.printStackTrace();
}
}
public void receiveMessage(UserIF topic) {
try {
if (session == null) {
connect();
}
destination = session.createTopic(topic.toString());
String nomAbonnement = topic.toString() + "-" + userSubscriber.toString();
consumer = session.createDurableSubscriber(destination, nomAbonnement);
consumer.setMessageListener(this);
} catch (JMSException e) {
e.printStackTrace();
}
}
public void unsubscribe(UserIF topic) throws JMSException {
try {
if (connection == null) {
connect();
}
System.out.println("\n RECEIVER Désinscription du topic " + topic.toString());
String nomAbonnement = topic.toString() + "-" + userSubscriber.toString();
System.out.println("\n RECEIVER Abonnement à clore = " + nomAbonnement);
consumer.close();
session.unsubscribe(nomAbonnement);
System.out.println("\n RECEIVER " + userSubscriber.toString() + " s'est désinscrit de " + nomAbonnement);
} catch (JMSException e) {
e.printStackTrace();
}
}
@Override
public void onMessage(Message message) {
System.out.println("\n RECEIVER OnMessage triggered for " + userSubscriber.toString());
listeMsg.add(message);
System.out.println("\n RECEIVER Nombre de messages reçus par " + userSubscriber + " = " + listeMsg.size());
String classe = message.getClass().getSimpleName();
System.out.println("\n RECEIVER Classe de message : " + classe);
try {
if (message instanceof TextMessage) {
TextMessage text = (TextMessage) message;
System.out.println("\n RECEIVER Information : " + text.getText());
}
if (message instanceof ObjectMessage) {
System.out.println("\n RECEIVER ObjectMessage");
ObjectMessage oMessage = (ObjectMessage) message;
if (oMessage.getObject() instanceof PostIF) {
PostIF post = (PostIF) oMessage.getObject();
String s = ((Post) post).getCorpsMessage();
System.out.println("\n RECEIVER Post : " + s);
}
}
} catch (JMSException e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws JMSException {
/*
* EACH USER IS A TOPIC FOR OTHER USERS
* WHATEVER A USER DOES RESULTS IN A NOTIFICATION TO SUBSCRIBERS
*/
//CREATE USER
UserIF u1, u2, u3;
String[] nom = new String[5];
String[] prenom = new String[5];
String[] login = new String[5];
String[] password = new String[5];
Date[] naiss = new Date[5];
String[] mail = new String[5];
for (int i = 0; i < 5; i++) {
nom[i] = "nom_" + i;
prenom[i] = "prenom_" + i;
login[i] = "login_" + i;
password[i] = "password_" + i;
naiss[i] = new Date();
mail[i] = "mail_" + i;
}
u1 = new User(nom[0], prenom[0], login[0], password[0], naiss[0], mail[0]);
u2 = new User(nom[1], prenom[1], login[1], password[1], naiss[1], mail[1]);
u3 = new User(nom[2], prenom[2], login[2], password[2], naiss[2], mail[2]);
/*
* MAKE EACH USER A SUBSCRIBER
*/
Receiver receiver1 = new Receiver(u1);
Receiver receiver2 = new Receiver(u2);
Receiver receiver3 = new Receiver(u3);
/*
* PUT A MESSAGE LISTENER FOR EACH USER
*/
receiver1.receiveMessage(u2);
receiver1.receiveMessage(u3);
receiver2.receiveMessage(u1);
receiver2.receiveMessage(u3);
receiver3.receiveMessage(u1);
receiver3.receiveMessage(u2);
receiver1.consumer.close();
receiver2.consumer.close();
receiver3.consumer.close();
/*
* CALL THE SENDER CLASS TO SEND MESSAGES
*/
try {
Sender.main(args);
} catch (Exception e1) {
e1.printStackTrace();
}
receiver1.unsubscribe(u2);
receiver2.unsubscribe(u3);
receiver3.unsubscribe(u1);
}
}