Groovy adds some nice operators to the language to write brief code. We already learned about the Elvis operator and the Spaceship operator. And now we see what the spread-dot operator is about and what it does.

link: Groovy Goodness: The Spread-Dot Operator – Messages from mrhaki

// Create a list with 3 objects. Each object has a lang
// property and a say() or sayIt() method.
def list [
    new Expando(lang: 'Groovy', say:   { "I am Groovy"}),
    new Expando(lang: 'Java',   sayIt: { "I am Java"}),
    new Expando(lang: 'Scala',  say:   { "I am ${lang}"})
]

// Use the spread-dot operator to invoke the say() method.
assert ['I am Groovy', 'I am Scala'] == list*.say()
assert ['I am Java'] == list*.sayIt()
assert ['I am Groovy', 'I am Scala'] == list.collect{ it.say() }

// We can also use the spread-dot operator to access
// properties, but we don't need to, because Groovy allows
// direct property access on list members.
assert ['Groovy', 'Java', 'Scala'] == list*.lang
assert ['Groovy', 'Java', 'Scala'] == list.lang

Concurrency is likely to be one of the main decision criteria when I chose which next language/platform to learn. I envision it being as important as memory management was when I started to learn OO and how it tipped the balance for Java instead of C++.

link: Jeff Mesnil » Blog Archive » Concurrency Is My New Memory Management Criteria

The Tiobe Groovy numbers show a sharp decline from the last month. It was biggest drop in percentage and in rank, and the lowest rating since I started keeping track.

link: Groovy/Grails Talk – July 2009 Groovy – Grails Job Market

There’s no need to edit any scripts – this is a maintenance problem since you’ll need to keep editing scripts each time you upgrade.
Just put:
app.context=/
in your application.properties

link: ]-[3ny0 ONLINE: Run grails-app on the root context

DirectJNgine is a Java based implementation of the Ext Direct API for ExtJs. DirectJNgine is feature complete, providing support for all kinds of requests: batched json requests, form posts with file uploads, requests from polling providers, etc. A detailed User’s Guide (more than 20 pages) is part of distribution. Besides, it runs all of Ext Direct examples distributed with ExtJs 3.0, located in examples/direct, and additional demos are included and discussed in the User’s Guide.

link: directjngine – Google Code

The documentation looks really good. I am excited to try out this new mechanism.

Upon first glance, it looks more cumbersome than my grails-like, spring mvc based, groovy controllers. Groovy makes it so simple to process dynamic data from the UI that I rarely need to worry much about marshalling and demarshalling. I do have to admit, though, that the method direct calling mechanism could definitely make the javascript code more readable. I’ll post about my experience after I try it.

Nuff said, here is the result of sorting 100.000 integers:

• Java: 45ms
• Scala: 60ms
• Groovy: 12800ms

link: Strongly Typed, Loosely Coupled: Java vs. Scala vs. Groovy – Performance Update

I decided to run his code on my box because the timings did not look right for what it was doing. As it turns out, his times were slow, but they were in the right proportion. Here is what I got (I didn’t run scala).

• Java: 10ms
• Groovy: 3828 ms

So, I decided to compare apples to apples and see what Ruby (another dynamic language) would come up with. I am not a ruby coder. I have tried it and that is about it. So, here is the quicksort routine I came up with:

def partition(data, front, back)
  last = front
  pivot = data[front]
  frontUnknown = front + 1

  while frontUnknown < = last do
    if data[frontUnknown] < pivot
      back += 1
      data[frontUnknown, back] = data[back, frontUnknown]
    end

    frontUnknown += 1
  end

  data[front, back] = data[back, front]
  back
end

def quicksort(data, front = 0, back = data.size - 1)
  if front < back
    pivotIndex = partition(data, front, back)
    quicksort(data, front, pivotIndex - 1)…

Grails is a fantastic framework. As well as being ultra-productive and fun to work with, it encourages good testing practices, and provides a swathe of tools to make writing unit, integration, and web tests a real pleasure. As we will see, Grails also lends itself quite well to build automation. However, Grails is not Maven. Grails has a fairly loose concept of the software development lifecycle, and is happy to let you bundle up and deploy your application as a WAR file without running all the unit and integration tests first. A Continuous Integration (CI) server can help you keep the flexibility of the Grails development process, and still ensure that your code is fully tested for each and every code change. In this article, we will take a look at how you can introduce Continuous Integration into your Grails project. More specifically, we will walk through how you can automate your Grails testing and code quality metrics with Hudson, a popular open source CI tool.

link: java.net: Grails and Continuous Integration: An Essential Combo

I somehow feel as if I have been initiated into some secret society: “The Knights Who Know About ”!

link: transentia pty. ltd. » Groovy Templating Follow-Up