Java

One thing I love about this blog site is the variety of developer-related topics - all created by the experts themselves! So, in case you missed any, here are the top 12 blog posting for 2013: 1. Setting up Django and Python 2.7 on Red Hat Enterprise 6 the easy way - This was the most popular article, by our developer evangelist, Langdon White. Great job, dude! 2. Released! Red Hat Software Collections now GA! - And here's the beta...

Photo by seeweb Countless products uses XML files, whether it is for data persistence, serialization or mere configuration. This is even more true when it comes to the Red Hat middleware portfolio, the JBoss projects having always been keen on using this format for configuration files - on top of the ones specified by JEE such as the famous (or infamous ?) web.xml. While the XML format has some definitive qualities, it is not the easiest format to parse, and...

In an earlier post we looked into using the Performance Co-Pilot toolkit to explore performance characteristics of complex systems. While surprisingly rewarding, and often unexpectedly insightful, this kind of analysis can be rightly criticized for being "hit and miss". When a system has many thousands of metric values it is not feasible to manually explore the entire metric search space in a short amount of time. Or the problem may be less obvious than the example shown - perhaps we...

Investigating performance in a complex system is a fascinating undertaking. When that system spans multiple, closely-cooperating machines and has open-ended input sources (shared storage, or faces the Internet, etc) then the degree of difficulty of such investigations ratchets up quickly. There are often many confounding factors, with many things going on all at the same time. The observable behaviour of the system as a whole can be frequently changing even while at a micro level things may appear the same...

For the really impatient reader: OpenJDK for AArch64 on Fedora is now available. Skip to the end of this blog for information about how you can get it. For everyone else: This is the first of my AArch64 OpenJDK blogs. I’m the project lead of the AArch64 OpenJDK port, and I’ll be blogging here from time to time. There may not be many people reading this blog who don’t know what AArch64 is, but it’s the new 64-bit version of...

How to change data in-flight, without a Debugger Do you ever wish you could change the behavior of some object in the middle of a bunch of method calls? I sometimes do. Maybe you want to set some properties on an object to replicate a fault. Maybe you’d like to force a specific return value from a method for some reason. These are both very possible, without altering the source code for your application. I like to do this through...

Over the past few years, I have been asked on and off as to what the process is for the RPMs that get into Red Hat Enterprise Linux and Fedora repositories. Over those years, the answer has evolved as we attempt to better the process. As it stands right now, there is a difference between how OpenJDK6, OpenJDK7 and OpenJDK8 (preview in Fedora 19) end up into RPMs. This post will shed some light into what those processes are. OpenJDK6...