I'm trying connect from a amqp client to a aqtivemq server with default settings. It always gives the error message saying connection refused. Then I tried it with a rabbitmq server instead of a activemq server and it works fine. I wonder whether activemq needs a linux library to communicate.
Activemq server versions used which does not connects: 5.4.2 / 5.10.0
Rabitmq version used: 3.3.5
rabitmq sample client code
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.Channel;
public class Cache {
private final static String QUEUE_NAME = "hello";
public static void main(String[] argv)
throws java.io.IOException {
//creating the connection factory
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
//Creating a connection to the server
Connection connection = factory.newConnection();
Channel channel = connection.createChannel();
//declaring a queuw
channel.queueDeclare(QUEUE_NAME, false, false, false, null);
String message = "Hello World!";
//publishing the queue the queue
channel.basicPublish("", QUEUE_NAME, null, message.getBytes());
System.out.println(" [x] Sent '" + message + "'");
//closing the connection
channel.close();
connection.close();
}
}
Fails in the following line of code
//Creating a connection to the server
Connection connection = factory.newConnection();
How can I solve this issue ?
I found a similar issue and I fixed checking the exchange declared was equals to the channel used to publish, in this way:
#Test
public void test() throws KeyManagementException, NoSuchAlgorithmException, URISyntaxException, IOException {
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("10.211.55.20");
factory.setPort(5672);
factory.setVirtualHost("/");
factory.setUsername("guest");
factory.setPassword("guest");
Connection connection = factory.newConnection();
Channel channel = connection.createChannel();
channel.exchangeDeclare("KipcastDirect", "direct",
true, /* durable */
true, /* autodelete */
null); /* */
byte[] messageBodyBytes = "Hello, world!".getBytes();
AMQP.BasicProperties.Builder basic = new AMQP.BasicProperties.Builder();
AMQP.BasicProperties minBasic = basic.build();
minBasic = basic.priority(0).deliveryMode(1).build();
channel.basicPublish("KipcastDirect", "KipcastRouting", minBasic, messageBodyBytes);
System.out.println(" [x] Sent ");
channel.close();
}
Please be carefoul: the URI (from and to) on Camel Spring DSL context and JUnit class must refer to same Exchange and Queue to prevent a reply-text=PRECONDITION_FAILED – parameters for queue ‘QUEUE’ in vhost ‘/’ not equivalen error or similar. To check the queues / exchanges configuration parameter use:
rabbitmqadmin -V / list queue
rabbitmqadmin -V test list exchanges
Take a look to this: http://www.andreagirardi.it/blog/camel-and-rabbitmq-finally-how-to/
Related
I'm studing how RabbitMQ works with Java, it is almost clear how Producer works and how to implement the Consumer, but I'm still not sure how to deploy the Consumer application to server with a correct threading handling.
Let's say I have a web-application that has to sent some transaction email as producer, this application will push in the queue the messages and it is managed by a container, like Tomcat, that increase/descrease threads to serve multiple requests.
What is the best practice to deployt the consumer application?
I have read many tutorials and the RabbitMQ commands are well explained, usually this is the code (from official RabbitMq Hello World):
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;
import java.nio.charset.StandardCharsets;
public class Recv {
private final static String QUEUE_NAME = "hello";
public static void main(String[] argv) throws Exception {
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
Connection connection = factory.newConnection();
Channel channel = connection.createChannel();
channel.queueDeclare(QUEUE_NAME, false, false, false, null);
System.out.println(" [*] Waiting for messages. To exit press CTRL+C");
DeliverCallback deliverCallback = (consumerTag, delivery) -> {
String message = new String(delivery.getBody(), StandardCharsets.UTF_8);
System.out.println(" [x] Received '" + message + "'");
};
channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> { });
}
}
However it is not clear to me how I should run this application in my server (sure I can start it by command line!) and how am I sure the process will not crash for some reason?
Should I put the channel opening commands in a loop inside a try/catch to be sure it will not exit?
Am I'm in charge of handling thread pool opening/increasing?
Does exists something for this purpose?
I am attempting to connect to RabbitMQ locally on port 15672 but am getting connection error. I am unsure what could be causing this as I am attempting to learn RabbitMQ... This is tutorial 1 I can't even get running. (https://www.rabbitmq.com/tutorials/tutorial-one-java.html)
Below is the code and error. The only changes from the tutorial I have made are specifying the port and username/password. Any ideas?
package send.java;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.Channel;
public class Send {
private final static String QUEUE_NAME = "hello";
public static void main(String[] argv) throws Exception{
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
factory.setPort(15672);
factory.setUsername("guest");
factory.setPassword("guest");
try (Connection connection = factory.newConnection(); Channel channel = connection.createChannel()){
channel.queueDeclare(QUEUE_NAME, false, false, false, null);
String message = "Hello World!";
channel.basicPublish("", QUEUE_NAME, null, message.getBytes());
System.out.println(" [x] Sent '" + message + "'");
}
}
}
Error
Exception in thread "main" java.io.IOException
at com.rabbitmq.client.impl.AMQChannel.wrap(AMQChannel.java:129)
at com.rabbitmq.client.impl.AMQChannel.wrap(AMQChannel.java:125)
at com.rabbitmq.client.impl.AMQConnection.start(AMQConnection.java:375)
at com.rabbitmq.client.impl.recovery.RecoveryAwareAMQConnectionFactory.newConnection(RecoveryAwareAMQConnectionFactory.java:64)
at com.rabbitmq.client.impl.recovery.AutorecoveringConnection.init(AutorecoveringConnection.java:156)
at com.rabbitmq.client.ConnectionFactory.newConnection(ConnectionFactory.java:1106)
at com.rabbitmq.client.ConnectionFactory.newConnection(ConnectionFactory.java:1063)
at com.rabbitmq.client.ConnectionFactory.newConnection(ConnectionFactory.java:1021)
at com.rabbitmq.client.ConnectionFactory.newConnection(ConnectionFactory.java:1182)
at send.java.Send.main(Send.java:15)
Caused by: com.rabbitmq.client.ShutdownSignalException: connection error
at com.rabbitmq.utility.ValueOrException.getValue(ValueOrException.java:66)
at com.rabbitmq.utility.BlockingValueOrException.uninterruptibleGetValue(BlockingValueOrException.java:36)
at com.rabbitmq.client.impl.AMQChannel$BlockingRpcContinuation.getReply(AMQChannel.java:502)
at com.rabbitmq.client.impl.AMQConnection.start(AMQConnection.java:317)
... 7 more
Caused by: java.io.EOFException
at java.base/java.io.DataInputStream.readUnsignedByte(DataInputStream.java:294)
at com.rabbitmq.client.impl.Frame.readFrom(Frame.java:91)
at com.rabbitmq.client.impl.SocketFrameHandler.readFrame(SocketFrameHandler.java:184)
at com.rabbitmq.client.impl.AMQConnection$MainLoop.run(AMQConnection.java:598)
at java.base/java.lang.Thread.run(Thread.java:832)
Port 15672 is the (default) HTTP port for the admin (management plugin) UI.
The default AMQP port is 5672.
How do I configure my J2EE application so that I can invoke ActiveMQ service along with tomcat server? I am aware about embedded broker, here asking how to start the ActiveMQ whenever I start tomcat
Current Code (works fine) :
Now I want to remove main() method and use the code to run when tomcat runs.
public class JMSService {
public void produceJMS() throws NamingException, JMSException {
ConnectionFactory connFactory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_BROKER_URL);
Connection conn = connFactory.createConnection();
conn.start();
Session session = conn.createSession(false,Session.AUTO_ACKNOWLEDGE);
Destination destination = session.createQueue("testQueue");
MessageProducer producer = session.createProducer(destination);
producer.setDeliveryMode(DeliveryMode.PERSISTENT);
TextMessage message = session.createTextMessage("Test Message ");
// send the message
producer.send(message);
System.out.println("sent: " + message);
}}
Here is my consumer :
public class JMSReceiver implements MessageListener,ExceptionListener {
public static void main(String args[]) throws Exception {
JMSReceiver re = new JMSReceiver();
re.receiveJMS();
}
public void receiveJMS() throws NamingException, JMSException {
ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_BROKER_URL);
Connection connection = connectionFactory.createConnection();
connection.start();
Session session = connection.createSession(false,Session.AUTO_ACKNOWLEDGE);
// Getting the queue 'testQueue'
Destination destination = session.createQueue("testQueue");
MessageConsumer consumer = session.createConsumer(destination);
// set an asynchronous message listener
JMSReceiver asyncReceiver = new JMSReceiver();
consumer.setMessageListener(asyncReceiver);
connection.setExceptionListener(asyncReceiver);
}
#Override
public void onMessage(Message message) {
System.out.println("Received message : " +message);
}
}
What #Tim Bish said is correct. You either need to have a timer say for example receiver should listen for 1 hour- or make it available until program terminate. Either case you need to start your consumer program once:
Change your receiveJMS method as follows:
public void receiveJMS() throws NamingException, JMSException {
try{
ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_BROKER_URL);
Connection connection = connectionFactory.createConnection();
connection.start(); // it's the start point
Session session = connection.createSession(false,Session.AUTO_ACKNOWLEDGE);
// Getting the queue 'testQueue'
Destination destination = session.createQueue("testQueue");
MessageConsumer consumer = session.createConsumer(destination);
// set an asynchronous message listener
// JMSReceiver asyncReceiver = new JMSReceiver();
//no need to create another object
consumer.setMessageListener(this);
connection.setExceptionListener(this);
// connection.close(); once this is closed consumer no longer active
Thread.sleep(60 *60 * 1000); // receive messages for 1 hour
}finally{
connection.close();// after 1 hour close it
}
}
The above program will listen upto 1 hour. If you want it as long as the program run, remove the finally block. But the recommended way is to close it somehow. since your application seems to be standalone ,you can check the java runtime shutdown hook, where you can specify how to release such resources while program terminates.
If your consumer is a web application you can close it in a ServletContextlistner.
You aren't giving the consumer application any time to actually receive a message, you create it, then you close it. You either need to use a timed receive call to do an sync receive of the message from the Queue or you need to add some sort of wait in the main method such as a CountDownLatch etc to allow the async onMessage call to trigger shutdown once processing of the message is complete.
I'm learning jms and found a sample Chat application but when i try running it, I get a security exception. It seems i need to pass in username and password when creating a new topic session, but the tutorial does not mention this.
Chat app code :
package ch02.chat;
import java.io.*;
import javax.jms.*;
import javax.naming.*;
public class Chat implements javax.jms.MessageListener {
private TopicSession pubSession;
private TopicPublisher publisher;
private TopicConnection connection;
private String username;
/* Constructor used to Initialize Chat */
public Chat(String topicFactory, String topicName, String username)
throws Exception {
// Obtain a JNDI connection using the jndi.properties file
InitialContext ctx = new InitialContext();
// Look up a JMS connection factory and create the connection
TopicConnectionFactory conFactory =
(TopicConnectionFactory)ctx.lookup(topicFactory);
TopicConnection connection = conFactory.createTopicConnection();
// Create two JMS session objects
TopicSession pubSession = connection.createTopicSession(
false, Session.AUTO_ACKNOWLEDGE);
TopicSession subSession = connection.createTopicSession(
false, Session.AUTO_ACKNOWLEDGE);
// Look up a JMS topic
Topic chatTopic = (Topic)ctx.lookup(topicName);
// Create a JMS publisher and subscriber. The additional parameters
// on the createSubscriber are a message selector (null) and a true
// value for the noLocal flag indicating that messages produced from
// this publisher should not be consumed by this publisher.
TopicPublisher publisher =
pubSession.createPublisher(chatTopic);
TopicSubscriber subscriber =
subSession.createSubscriber(chatTopic, null, true);
// Set a JMS message listener
subscriber.setMessageListener(this);
// Intialize the Chat application variables
this.connection = connection;
this.pubSession = pubSession;
this.publisher = publisher;
this.username = username;
// Start the JMS connection; allows messages to be delivered
connection.start();
}
/* Receive Messages From Topic Subscriber */
public void onMessage(Message message) {
try {
TextMessage textMessage = (TextMessage) message;
System.out.println(textMessage.getText());
} catch (JMSException jmse){ jmse.printStackTrace(); }
}
/* Create and Send Message Using Publisher */
protected void writeMessage(String text) throws JMSException {
TextMessage message = pubSession.createTextMessage();
message.setText(username+": "+text);
publisher.publish(message);
}
/* Close the JMS Connection */
public void close() throws JMSException {
connection.close();
}
/* Run the Chat Client */
public static void main(String [] args) {
try {
if (args.length!=3)
System.out.println("Factory, Topic, or username missing");
// args[0]=topicFactory; args[1]=topicName; args[2]=username
Chat chat = new Chat(args[0],args[1],args[2]);
// Read from command line
BufferedReader commandLine = new
java.io.BufferedReader(new InputStreamReader(System.in));
// Loop until the word "exit" is typed
while(true) {
String s = commandLine.readLine();
if (s.equalsIgnoreCase("exit")){
chat.close();
System.exit(0);
} else
chat.writeMessage(s);
}
} catch (Exception e) { e.printStackTrace(); }
}
}
I have the following jndi.properties file in my classpath:
java.naming.factory.initial = org.apache.activemq.jndi.ActiveMQInitialContextFactory
java.naming.provider.url = tcp://localhost:61616
java.naming.security.principal=system
java.naming.security.credentials=manager
connectionFactoryNames = TopicCF
topic.topic1 = jms.topic1
Active mq is running (I can access the admin console). And this is the error that i get when running this app and passing parameters 'TopicCF topic1 Fred':
javax.jms.JMSException: User name [null] or password is invalid.
at org.apache.activemq.util.JMSExceptionSupport.create(JMSExceptionSupport.java:49)
at org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1391)
at org.apache.activemq.ActiveMQConnection.ensureConnectionInfoSent(ActiveMQConnection.java:1496)
at org.apache.activemq.ActiveMQConnection.createSession(ActiveMQConnection.java:325)
at org.apache.activemq.ActiveMQConnection.createTopicSession(ActiveMQConnection.java:1122)
at ch02.chat.Chat.<init>(Chat.java:47)
at ch02.chat.Chat.main(Chat.java:105)
Caused by: java.lang.SecurityException: User name [null] or password is invalid.
at org.apache.activemq.security.SimpleAuthenticationBroker.addConnection(SimpleAuthenticationBroker.java:81)
at org.apache.activemq.broker.MutableBrokerFilter.addConnection(MutableBrokerFilter.java:91)
at org.apache.activemq.broker.TransportConnection.processAddConnection(TransportConnection.java:766)
at org.apache.activemq.broker.jmx.ManagedTransportConnection.processAddConnection(ManagedTransportConnection.java:79)
at org.apache.activemq.command.ConnectionInfo.visit(ConnectionInfo.java:139)
at org.apache.activemq.broker.TransportConnection.service(TransportConnection.java:329)
at org.apache.activemq.broker.TransportConnection$1.onCommand(TransportConnection.java:184)
at org.apache.activemq.transport.MutexTransport.onCommand(MutexTransport.java:50)
at org.apache.activemq.transport.WireFormatNegotiator.onCommand(WireFormatNegotiator.java:113)
at org.apache.activemq.transport.AbstractInactivityMonitor.onCommand(AbstractInactivityMonitor.java:288)
at org.apache.activemq.transport.TransportSupport.doConsume(TransportSupport.java:83)
at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:214)
at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:196)
at java.lang.Thread.run(Thread.java:745)
I don't yet have topic1 created anywhere, but that should throw a different exception.
The credentials that you log in with to the broker are defined in the JMS API when you establish a connection. To pass in a username and password, do the following:
TopicConnection connection =
conFactory.createTopicConnection(username, password);
The correct way is, as menstioned by Jake, to use the topic connection factory constructor with username and password :
TopicConnection connection =
conFactory.createTopicConnection(username, password);
There is another option, in activemq we can allow anonymous access by adding the simple authentication plugin in activemq.xml configuration file and setting anonymousAccessAllowed="true".
<broker xmlns="http://activemq.apache.org/schema/core" brokerName="localhost" dataDirectory="${activemq.data}" schedulerSupport="true">
<plugins>
<!-- users and passwords -->
<simpleAuthenticationPlugin anonymousAccessAllowed="true">
<users>
<authenticationUser username="system" password="manager" groups="admins,publishers,consumers" />
</users>
</simpleAuthenticationPlugin>
</plugins>
In my RabbitMQ app the producer sends messages, but consumer receives only part of them(not the biggest one). when I execite rabbitmqctl list_queues in terminal it shows:
~$ sudo rabbitmqctl list_queues
Listing queues ...
MdnaMessagesQueue 0
...done.
which means that messages are lost going to the queue or they were taken from the queue very fast. so I can't understand why this happens. I have no other apps which could get messages from that queue. here is my producers code:
public class Sender {
private static final String QUEUE_NAME = "MdnaMessagesQueue";
public void send(byte[] message) throws IOException {
AMQP.BasicProperties.Builder bob = new AMQP.BasicProperties.Builder();
AMQP.BasicProperties minBasic = bob.build();
AMQP.BasicProperties minPersistentBasic = bob.deliveryMode(2).build();
ExecutorService service = Executors.newFixedThreadPool(10);
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
Connection connection = factory.newConnection(service);
Channel channel = connection.createChannel();
channel.queueDeclare(QUEUE_NAME, true, false, false, null);
channel.basicPublish("", QUEUE_NAME, MessageProperties.PERSISTENT_TEXT_PLAIN, message);
channel.close();
connection.close();
}
}