OO Hello World - Kotlin

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The OO Hello World in Kotlin, the "the new language from JetBrains for the JVM", is here!

Project Kotlin is a codename for a statically typed programming language compiled to JVM byte code and JavaScript.

You can see the OO Hello World series post here: http://carlosqt.blogspot.com/2010/06/oo-hello-world.html where I give some details on why these "oo hello world series" samples.

Version 1 (Minimal):

The minimum you need to type to get your program compiled and running.

class Greet(name : String) {
  val name : String = name[0].toString().toUpperCase() + name.substring(1, name.length);
  fun salute() {
    println("Hello, ${name}!");
  }
}

// Greet the world!
fun main(args : Array<string>) {
  val g = Greet("carlos");
  g.salute();
}

Version 2 (Verbose):

Explicitly adding instructions and keywords that are optional to the compiler.

package greetprogram;

public class Greet(name : String) {
  private val name : String = name[0].toString().toUpperCase() + name.substring(1, name.length);
  public fun salute() {
    println("Hello, ${this.name}!");
  }
}

public fun main(args : Array<string>) {
  val g = Greet("carlos");
  g.salute();
}

The Program Output:

Kotlin Info:

""Project Kotlin" is the codename of a statically-typed JVM-targeted programming language developed by JetBrains intended for industrial use. This is an object-oriented language” Taken from: ( http://confluence.jetbrains.net/display/Kotlin/Welcome )

Appeared:	2011
Current Version:	0.1 (latest version in "Languages" page)
Developed by:	JetBrains
Creator:	Andrey Breslav
Influenced by:	Groovy (Guillaume Laforge), C# (Anders Hejlsberg) Java (James Gosling), Scala (Martin Odersky)
Predecessor Language	N/A
Predecessor Appeared	N/A
Predecessor Creator	N/A
Runtime Target:	JVM
Latest Framework Target:	JDK 6
Mono Target:	No
Allows Unmanaged Code:	No
Source Code Extension:	“.kt”
Keywords:	31
Case Sensitive:	Yes
Free Version Available:	Yes
Open Source:	Yes
Standard:	N/A
Latest IDE Support:	Intellij IDEA https://github.com/JetBrains/kotlin/downloads
Language Reference:	http://confluence.jetbrains.net/display/Kotlin/Docs+Home
Extra Info:	http://blog.jetbrains.com/kotlin/ http://kotlin-demo.jetbrains.com/