Interesting Links – 2017/May/25

  • How Fonts are Fueling the Culture Wars is an article talking about, well, font usage and what specific fonts mean, which has only a tangential relation to Java — but think about it in terms of user experience, too. Do you think the user experience of Java communicates a specific mode of thought? If so, what would it be? (And no, “Duhhhh” is not a valid answer!)
  • From DZone: The Soon-to-Be-Hated Object Locator presents a pattern for a type of God Object, except possibly restricted in scope enough to not earn the full derision that a God Object deserves… maybe.
  • Also from DZone: The Genius of the Law of Demeter, an article with far less controversy than a God Object would create. The short form of the Law of Demeter says that you call methods on objects that your class owns directly: this.getFoo().bar() is okay, but this.getFoo().getBar().baz() is not (and, as usual, there’s more to it than this.)
  • Stack Overflow: Helping One Million Developers Exit Vim documents the usage patterns for questions that … help developers exit vim. Vim isn’t especially common for Java developers (although it happens) – but still! What a great editor! How user-friendly does an editor have to be that one in 20000 visits to Stack Overflow is specifically about how to exit the editor? (And now I wonder how many visits are about exiting Emacs, too…)
  • Java 9 expert group minutes: – it’s good to keep up on the current status, because the implications of every choice made are pretty serious. The second set of minutes are also available.
  • vJUG24 is back! (… I didn’t know what this was until someone sent it to me.)

Interesting Links – 22/May/2017

  • Github gets an App Store.
  • Jenetics is an advanced Genetic Algorithm, respectively an Evolutionary Algorithm, library written in modern day Java.
  • Need to run things before or after your unit test executes? Don’t forget the lifecycle annotations, for TestNG and JUnit.

Interesting Links – 8/May/2017

DropWizard Metrics Advice

I was working on an application with DropWizard, and I was having trouble getting my own metrics to show up in the display. The Metrics Getting Started is useful, and it actually showed me what I needed, but didn’t make it obvious enough for me.
What I needed was, in DropWizard Metrics parlance, a “meter.” This gives me performance data over time; basically, every time an event happens, I’d mark it and thus be able to see how busy the system was in the last minute, the last five minutes, and the last 15 minutes.
I followed the Metrics Getting Started:

  • I got a MetricsRegistry (by using new MetricsRegistry())
  • I created a Meter by calling register.meter(name) if necessary (and stored the Meter in a map so I could retrieve it again at will)
  • I marked an event by calling Meter.mark()

But at no point was I able to see the meter displayed in the DropWizard servlet.
The reason is because I created my own MetricsRegistry. One right way to do it is documented; it’s to use SharedMetricRegistries.getDefault(); instead (which gets you a MetricsRegistry that is displayed automatically).
Note that the DropWizard documentation is not wrong – it just steps past something that most people probably want by default.

Interesting Links – 2017/May/1

If you have a teammate who suffers from mental illness, I’d encourage you to champion (heart and balance) within your team. Be an ally. Help create a safe and inclusive space. Not only because it’s the right thing to do, but because being around people different from you broadens your horizons and builds empathy. And empathy for others makes you better at just about every job.