How do I view messages in ActiveMQ?
How can I monitor ActiveMQ
- JMX and a JMX console such as jConsole.
- The Web Console.
- the Advisory Message feature (using JMS messages to monitor the system)
- The Command Agent; ActiveMQ.Agent topic that you query for status.
- The Visualisation plug-in.
- The Statistics plug-in (from 5.3)
What is a topic in ActiveMQ?
ActiveMQ topic is a pipeline of messages where a message comes in and goes to every subscriber. Both ActiveMQ queue and ActiveMQ topic are places where messages are sent. The difference is in who receives the message.
How do I view ActiveMQ queues?
You can view the queue depth using the MBeans in ActiveMQ 5. x. Use any JMX management console to see the statistics.
What is the difference between a queue and a topic?
The main difference between queue and topic is that queue is the message-oriented middleware used in point to point message domain while the topic is the message-oriented middleware used in publisher-subscriber message domain.
How do I purge messages in ActiveMQ?
You can do tweak your activemq. xml a bit: <broker deleteAllMessagesOnStartup=”true” …> This works with KahaDB message stores (it has problems with JDBC message stores), all your messages get deleted and subsequently queues are cleared.
How do I read my JMS messages?
To View Message Properties
- Select the topic or queue as described in Monitoring Topics and Queues for JMS IQ Manager.
- In the Messages tab, select the message and click the Properties icon. The View Message Property dialog box appears. The following table describes the message properties.
- When you are done, click Close.
What is a message topic?
A sibling to a message queue, a message topic provides a lightweight mechanism to broadcast asynchronous event notifications, and endpoints that allow software components to connect to the topic in order to send and receive those messages.
What is topic in messaging system?
A topic is the subject of the information that is published in a publish/subscribe message. Messages in point-to-point systems are sent to a specific destination address. In content-based systems, messages are sent to subscribers based on the contents of the message itself. …
How do you purge a queue?
Click the Queue tab and go to the bottom of the page. You will find a dropdown “Delete / Purge” there. Press Purge to the right to empty the queue.
Is ActiveMQ pub sub?
In the case of the point-to-point messaging ActiveMQ works as a load balancer. It routes each message from the queue to one of the available consumers. Meanwhile, if you prefer the “pub/sub” messaging, the system delivers each message to every consumer subscribed to the topic.
What is message Dequeued in ActiveMQ?
dequeued messages = messages delivered from the destination to consumers. this number can be higher that the number of enqueued messages if a message was delivered to multiple consumers (topics).
How are queues different from topics in ActiveMQ?
While the producer sends messages to a topic, consumers will receive a copy of the message on their own dedicated queue. Multiple consumers can get a message Decoupling between producer and consumers (publish-and-subscribe pattern) Messages can be recovered by putting them back on the queue
Which is the best messaging pattern in ActiveMQ?
Queues. Queues are the most obvious messaging pattern implemented by ActiveMQ. They provide a direct channel between a producer and a consumer. The producer creates messages, while the consumer reads one after another. After a message was read, it’s gone. If multiple consumers are registered for a queue, only one of them will get the message.
When to unmarshal a message in ActiveMQ?
ActiveMQ does not unmarshal messages when receiving them (for performance reasons, unmarshalling is rather expensive). Thus, if you want to have some way to inspect messages for their content, you can basically do 2 things: Write a consumer which registers for all topics/queues, through which you can see messages’ content.
How can I write a plugin for ActiveMQ?
Write an activeMQ plugin which looks at the messages. Have a look at ActiveMQ’s Logger Plugin. Then write your own (you’ll need the sources to compile it) and load it with ActiveMQ (see the documentation on how to configure ActiveMQ to load plugins).
