Saturday, April 11, 2009

Learning Scala 1 : A Hello World

Scala is a powerful and interesting language to learn. Personally, I like it as the next generation of my daily written Java programming language.

To getting started with Scala is easy. Get a Scala distribution from http://www.scala-lang.org and unzip it to, for say C:\scala-2.7.3.final and set C:\scala-2.7.3\bin into your PATH environment variable. It requires Java runtime environment version 1.5 or later installed on your machine, I am having Sun JDK 6 Update 13 installed on my Windows XP machine.

After the above setup, you can start Scala Interpreter by entering 'scala' in command prompt:-


C:\>scala


Alternatively, you can start the Scala Interpreter also by double clicking 'scala.bat' under the 'bin' folder. You should after the Scala Interpreter waiting for your command now:-


scala>


Now, let's type 3 + 5 into it:-


scala> 3 + 5
res0: Int = 8


The 'res0' is a generated name to refer to the calculated value. You can try to print it out by using println():-


scala> println(res0)
8


You can declare 'val' (value) or 'var' (variable) in Scala, 'val' works similar like 'final' in Java, which reassignment is not allowed. You can try reassign the 'res0' to something else and you should get an error:-


scala> res0 = 9
:5: error: reassignment to val
res0 = 9


Now, let's declare a value call 'myValue':-


scala> val myValue = "Hello World"
myValue: java.lang.String = Hello World


You can see that I do not declare any type for myValue, the Scala compiler is smart enough to infer the value type to String, optionally, you can write it in the following way:-


val myValue:String = "Hello World"


Now, let's print it out:-


scala> println(myValue)
Hello World


That's complete my 'Hello World' in Scala!. ;-)

Friday, March 27, 2009

ACE for Flex 3 with AIR Exam Cleared

After a week of intensive reading after working hours, finally I got it through today with 92%. The preparation process was tough for me as the scope seems to be very wide. I studied mainly using the official materials from Adobe, which include:

Adobe Flex 3 Developer Guide
Developing Adobe AIR Applications With Adobe Flex 3
BLAZEDS Developer Guide

I didn't study for ActionScript programming as I am coding it in my daily job. ;-)

Looking forward to have a great weekend, Cheers!

Friday, January 9, 2009

'Work In Progress' Animated GIF Generator

I am looking for an nice icon to indicate 'Work in Progress' GIF today and found a nice site which let you customize and generate 'Work in Progress' animated GIF:-

http://www.ajaxload.info

Customize indicator type, colors and transparency.








Generated GIF with 'Bar' indicator: