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Journey to the Center of JRuby

pat_shaughnessy — Tue, 07 Feb 2012 19:24:26 +0000

This week I decided to take a look at JRuby, which is a Java implementation of the Ruby interpreter. I’ve heard great things about JRuby, but had never taken the time before to look at how it works internally. What I found was an amazingly complex system involving many different technologies. Following the path of execution through the JRuby stack was like peeling away different layers of...

Martin Fowler: The Future is not just NoSQL, it's Polyglot Persistence

martinfowler — Tue, 07 Feb 2012 17:31:31 +0000

The NoSQL v. SQL argument has been beaten (almost) to death, and now it's time to look forward to the foggy future of the data storage and access. Martin Fowler and Pramod Sadalage have s recently released a slick infodeck tracing a simple history of databases, as well as their own prophecy of where databases are headed, namely Polyglot Persistence, or: "Using multiple data storage...

Algorithm of the Week: Data Compression with Prefix Encoding

stoimen — Tue, 07 Feb 2012 14:57:43 +0000

Prefix encoding, sometimes called front encoding, is yet another algorithm that tries to remove duplicated data in order to reduce its size. Its principles are simple, however this algorithm tends to be difficult to implement. To understand why, first let’s take a look at its nature. Have a look on the following dictionary.useusedusefulusefulnessuselssuselesslyuselessness ...

Findability is So Last Year

trussellrose — Tue, 07 Feb 2012 13:12:42 +0000

Preview Text: Search is more than just findability. So why the fixation with findability? Out of 104 enterprise search scenarios, less than 2% were categorised as findability tasks. In this post you will learn about the broader, overall information goals for most search efforts. Mitchell...

Code coverage is a side effect and not an end goal

sandromancuso — Tue, 07 Feb 2012 06:36:43 +0000

In my previous life as a consultant, one of our clients hired us to "increase the code coverage" of their code base. We would not develop any new features or make any changes. They just wanted us to write tests. Basically they wanted us to bring the coverage up to 70%. Why 70% you may ask. Probably because someone pulled a finger out of his or her back orifice, sniffed it and...

DaliCore on java.net

jv59641 — Tue, 07 Feb 2012 05:58:37 +0000

After years of development, refactoring, brainstorms, projects, fun, more refactoring,... we open-sourced the DaliCore code. DaliCore creates the core for the social networking applications that we developed with LodgON over the past years. Some code and documentation is now available on http://java.net/projects/dalicore and we will be adding more code and documentation gradually. Most of the...

Troubleshooting Jersey REST Server and Client

malyvelky — Tue, 07 Feb 2012 05:56:19 +0000

The logging in Jersey, the reference JAX-RS implementation, is little sub-optimal. For example if it cannot find a method producing the expected MIME type then it will return “Unsupported mime type” to the client but won’t log anything (which mime type was requested, which mime types are actually available, …). Debugging it isn’t exactly easy either, so what to do? Well, I...

JavaFX 2 Presents the Quadratic Formula

java_dm — Tue, 07 Feb 2012 05:54:22 +0000

I recently needed to check some homework answers related to use of the quadratic formula. After realizing that it was getting tedious to do these by hand, I thought of using my calculator to solve them. However, I realized that I could write a simple application using JavaFX to calculate the results and that approach seemed more interesting than using the calculator. Preview Text: ...

Code reviews in the 21st Century

dublintech — Tue, 07 Feb 2012 05:53:01 +0000

There's an old adage that goes something like: 'Do not talk about religion or politics'. Why? Because these subjects are full of strong opinions but are thin on objective answers. One person's certainty is another person's skepticism; someone else's common sense just appears as an a prior bias to those who see matters differently. Sadly, conversing these controversial subjects...

Autowiring Using @Value and Optional Properties

CaptainDebug — Tue, 07 Feb 2012 05:00:36 +0000

Last October I wrote a blog entitled Autowiring Property Values into Spring Beans describing how to use Spring’s @Value annotation to inject property values into your beans from both a property file and Java system properties. Last week, I came across this little gotcha whilst helping out on another project.... Preview Text: Last October I...

Poll: Which HTML5 Refcard Would You Like To See Next?

johnesposito — Mon, 06 Feb 2012 16:12:56 +0000

So it looks like our new HTML5 Canvas Refcard proved interesting to you, our excellent DZone readers. Our general HTML5 Refcard has received a lot of downloads too -- so we've decided to go all-out and publish a whole series of Refcardz on emerging web technologies. The massive tangle of new features, APIs, etc. that generally goes by 'HTML5' (whether...

Make your process your Rock Star, not individuals

anichols — Mon, 06 Feb 2012 12:51:28 +0000

I recall a few jobs ago I was managing the Systems Engineering team and trying to grow it into a group that could handle the daily onslaught of issues that would plague our service. We had recruiters working on sourcing folks & we felt like we had very high standards for who we wanted to hire. We talked to and turned away probably hundreds of folks it felt like (I got really good at...

Document language identification

gr0 — Mon, 06 Feb 2012 12:36:01 +0000

One of the features of the latest Solr version (3.5) is the ability to identify the language of the document during its indexation. In today's entry we will see how Apache Solr works together with Apache Tika to identify the language of the documents. At the beginning You should remember that the described functionality was introduced in Solr 3.5. Preview Text: ...

Java.lang.VerifyError: Expecting a stackmap frame at branch target – JDK 7

veerasundark — Mon, 06 Feb 2012 05:51:38 +0000

Right now, when I try to persist an object in Google App Engine, I’m facing the error “Java.lang.VerifyError: Expecting a stackmap frame at branch target“. I’m using JDK 7 and it seems like the problem lies with this JDK. After googling a bit, I found that there seems to be two solutions to fix this problem. Solution 1: Change to JDK 6 As simple as is, change your JDK to version 6 and you...

Documentation that is useful

jexenberger — Mon, 06 Feb 2012 05:49:48 +0000

I was reading this article by Neil Mcallister on his Fatal Exception blog entitled "How to get developers to document their code". Now it begs the question: What documentation is actually useful? Well, like all things in general I don't think it's a simple answer, best I could say is; what works well in your context. Preview Text: I...