FAQ
Here are a list of commonly asked questions and answers. If you have any questions which are not on this list, please contact us.
General
General questions about ActiveMQ Classic
- Can I get commercial support
- How can I get the source code from subversion
- How does ActiveMQ Classic compare to AMQP
- How does Classic compare to Artemis
- How does ActiveMQ Classic compare to Fuse Message Broker
- How does ActiveMQ Classic compare to JBossMQ
- How does ActiveMQ Classic compare to Mantaray
- How does ActiveMQ Classic compare to Mule
- How does ActiveMQ Classic compare to Spread Toolkit
- How does OpenWire compare to Stomp
- How do I avoid Maven downloading latest jars
- How do I build but disable the unit tests
- How do I compile from the source
- How fast is ActiveMQ Classic
- Should I run ActiveMQ Classic on Windows in a directory with spaces
- What is ActiveMQ Classic
- What is the license
- What jars do I need
- What open source integration solution works best with ActiveMQ Classic
- What platforms does ActiveMQ Classic support
- What version should I use
JMS
Questions on using the JMS API and MOM in general
- Can I modify messages on a queue
- Can I send and receive messages concurrently on one JMS Connection
- Can you browse a topic
- How do durable queues and topics work
- How does a Queue compare to a Topic
- How does ConnectionFactory relate to the Broker
- How does JMS compare with email
- How do I consume a specific message
- How do I get started with JMS
- How do I make messages durable
- How do I send messages to different Destinations from a single MessageProducer
- How do I use JMS efficiently
- How should I implement request response with JMS
- How To Unit Test JMS Code
- Multiple consumers on a queue
- Should I use transactions
- Should I use XA
- What are administered objects
Using Apache ActiveMQ Classic
Questions on using Apache ActiveMQ Classic
- ActiveMQ Classic Command Line Tools Reference
- Are destinations case sensitive
- Can I send really large files over ActiveMQ Classic
- Can I use ActiveMQ Classic 5.x or later on Java 1.4
- Can two brokers share the same database
- Does ActiveMQ Classic support clustering
- How can I avoid serialization of Objects in ObjectMessage
- How can I get a list of the topics and queues in a broker
- How can I make ActiveMQ Classic faster
- How can I monitor ActiveMQ Classic
- How can I monitor the connection with the broker
- How can I see what destinations are used
- How can I support auto reconnection
- How can I support priority queues
- How can I use different network protocols
- How do distributed queues work
- How do I access ActiveMQ Classic from C
- How do I access ActiveMQ Classic from CSharp or dotNet
- How do I access ActiveMQ Classic from Ruby, Perl, Python, PHP
- How do I bridge different JMS providers
- How do I change dispatch policy
- How do I change the logging
- How do I connect to one of a number of message brokers
- How do I create new destinations
- How do I delete a destination
- How do I disable logging
- How do I embed a Broker inside a Connection
- How do I enable asynchronous sending
- How do I enable debug logging
- How do I find the Size of a Queue
- How do I preserve order of messages
- How do I purge a queue
- How do I restart embedded broker
- How do I restrict connections from creating new queues or topics
- How do I run a broker
- How do I set the message expiration
- How do I turn off creating an embedded ActiveMQ Classic broker when using the VM transport
- How do I unack the message with Stomp
- How do I use ActiveMQ Classic using in JVM messaging
- How do I use durable subscribers in a network of brokers
- How do I use Ivy with ActiveMQ Classic
- How do I use log4j JMS appender with ActiveMQ Classic
- How do I use SSL
- How do Message Groups compare to Selectors
- How do multiple transports work
- How Do Transactions Work
- How lightweight is sending a message
- How should I package applications using Camel and ActiveMQ Classic
- How should I use the VM transport
- How to deal with large number of threads in clients
- How to disable auto destination creation
- I see NC_ client-ids, what does that mean
- Should I deploy Enterprise Integration Patterns in the broker or another application
- Should I deploy the broker inside my JVM or AppServer
- What are those topics ActiveMQ.Advisory
- What happens with a fast producer and slow consumer
- What is the difference between a Virtual Topic and a Composite Destination
- What is the difference between discovery, multicast and zeroconf
- What is the Prefetch Limit For?
- While posting large binary file to activeMQ, is there a way to measure its progress
Configuration
Questions on configuring ActiveMQ Classic’s JMS client or the Message Broker
- How can I enable detailed logging
- How does XBean compare to Spring 2
- How do I configure 10s of 1000s of Queues in a single broker
- How do I configure ActiveMQ Classic to hold 100s of millions of Queue Messages
- How do I configure ActiveMQ Classic to use AIO server transport
- How do I configure automatic reconnection
- How do I configure distributed queues or topics
- How do I configure the queues I want
- How do I define a local address and local port for TCP or SSL
- How do I disable persistence
- How do I run ActiveMQ Classic under the Kaffe JVM
- How to configure a new database
- How to deploy activemq-ra-version.rar to weblogic
- How to disable multicast discovery
Persistence Questions
Questions relating to long term persistence of messages.
- Are messages read directly from the journal
- Does ActiveMQ Classic support my SQL database
- How does journaling work with multiple brokers
- How does the journal work
- How do I back-up KahaDB
- How do I change the message store directory for an embedded broker
- Is there a specified size of the journal
- What happens when the journal size is exceeded
- What is the difference between persistent and non-persistent delivery
Errors
Questions on specific kinds of errors. If you have seen a specific exception then check the Exceptions
- Could not find PacketReader for packet type - UNKNOWN PACKET TYPE
- Exceptions
- certificate_unknown
- IOException - could not find class for resource
- java.io.InterruptedIOException
- java.io.IOException Failed to create database ‘derbydb’, see the next exception for details
- java.lang.NoSuchMethodError
- java.lang.NoSuchMethodException org.activemq.ra.ActiveMQResourceAdapter.setUseEmbeddedBroker
- java.lang.OutOfMemory
- javax.jms.JMSException - Wire format negociation timeout - peer did not send his wire format.
- JAXB 2.0 API is being loaded from the bootstrap classloader, but this RI () needs 2.1 API.
- JAXB 2.0 API is being loaded from the bootstrap classloader, but this RI (xxx) needs 2.1 API
- Journal is already opened by this application
- NoClassDefFoundError - org.springframework.core.io.Resource
- No suitable driver
- I am having problems with the Spring JmsTemplate
- I am not receiving any messages, what is wrong
- I cannot connect to ActiveMQ Classic from JConsole
- I do not receive messages in my second consumer
- I get errors building the code whats wrong
- log4j-WARN No appenders could be found for logger
- Multicast - Watch out for IPV6 vs IPV4 support on your operating system or distribution or network
- My producer blocks
- onMessage method of MessageListener is never called
- Resource Adapter does not seem to pool connections
- Slow networks drop large messages
- The Broker will not start
- The vm transport starts a broker before my configured broker starts
- Why do I not get all of the messages I sent
- Why do I not receive messages on my durable topic subscription
- Why do KahaDB log files remain after cleanup
Developing ActiveMQ Classic
Questions for developers wishing to extend or enhance Apache ActiveMQ Classic
- How can I add a new type of transport
- How can I contribute
- How do I add my own plugins
- How do I debug ActiveMQ Classic from my IDE
Terminology
A list of the various messaging related terms and acronyms.