Category — nuggets

http://books.dzone.com/reviews/activemq-action

Building ActiveMQ networks of brokers is a handy way to eliminate the need of making application deal with network outage. If the application lives on the same server or highly reliable network as the broker, then there is no need to implement network based error handling. However often consumers are remote and they also do not want to deal with network connectivity and those consumers may choose to implement their own broker. Connecting brokers then allows brokers to deal with intermittent networks and transmit messages whenever possible while exposing always on interface to local customers.

In his new tutorial @ripienaar covers how how to build ActiveMQ networks of brokers, so check it out.

You if you have been convinced by a blog entry from yesterday not to use ActiveMQ for building a chat application. Here is tutorial on how to setup a chat server in 10 minutes.

Responding to a blog entry by Stephan Schmidt (@codemonkeyism on twitter). Stephan compares the Jabber and ActiveMQ to decide which one suits better his projects needs. While both products fulfill the asynchronous messaging criteria, they have been designed and built for substantially different purposes. Below are some guidelines when to use ActiveMQ or other enterprise messaging products such as JBoss Messaging or WebSphere MQ.

Use Enterprise Messaging if project requires:

• Transactional Support
• Message Persistence and Media Recovery (Transactional Logs)
• Large Messages (4MB+)
• Competing Consumers
• Coded Character Set Conversions
• Clustering
• Blocking (Non-polling wait)
• Storing potentially millions of messages on the queue
• Message Expiration
• Multiple Qualities of Server
• Server-to-Server Channels
• Hierarchical Publish Subscribe Topic Namespace
• FIFO or Priority Queues

Use Jabber or other instant messaging protocol when you’re building a chat application. Yes. It is that simple. Here are good indicators using Jabber might be ok are:

• Messages have no or minimal business value. (They are not business transactions)
• Messages are small
• Transactional support is not necessary
• You need a simple transport(HTTP) that can work across VPN’s, Proxies and Firewalls.
• Messages have no affinity.
• Simple Message Patterns (One-to-one, One-to-many)

Hiram Chirino posted on his blog a benchmark results of a ActiveMQ supported protobuf patch that looks substantially faster than existing solutions such as Google’s protobuf and thrift. For more details, you can subscribe to Hiram’s Blog or follow him on twitter @hiramchirino

This paper was published by James Strachan and provides excellent summary overview of ActiveMQ usage in enterprise middleware.

This excellent book review provides chapter by chapter summary of the most recent Manning ActiveMQ In Action Book. You can follow the review blogger @jbandi on twitter

Terry Palmer of cfteeps posted(via @hgz) a configuration on maintaining channels. I would also recommend increasing TCP KeepAlive interval.

The reference configuration can be found here Provided configuration uses multicast and allows client to discover available queue managers eliminating single point of failure and allowing consumer or a producer to work with multiple queue managers if necessary. Similar technology is available via JGroups in JBoss Messaging.