App

scala.App
trait App extends DelayedInit

The App trait can be used to quickly turn objects into executable programs. Here is an example:

object Main extends App {
  Console.println("Hello World: " + (args mkString ", "))
}

No explicit main method is needed. Instead, the whole class body becomes the “main method”.

args returns the current command line arguments as an array.

Caveats

It should be noted that this trait is implemented using the DelayedInit functionality, which means that fields of the object will not have been initialized before the main method has been executed.

Future versions of this trait will no longer extend DelayedInit.

Attributes

Source:
App.scala
Graph
Supertypes
class Object
trait Matchable
class Any

Members list

Concise view

Value members

Concrete methods

final protected def args: Array[String]

The command line arguments passed to the application's main method.

The command line arguments passed to the application's main method.

Attributes

Source:
App.scala
final def main(args: Array[String]): Unit

The main method.

The main method. This stores all arguments so that they can be retrieved with args and then executes all initialization code segments in the order in which they were passed to delayedInit.

Attributes

args

the arguments passed to the main method

Source:
App.scala

Deprecated methods

override def delayedInit(body: => Unit): Unit

The init hook.

The init hook. This saves all initialization code for execution within main. This method is normally never called directly from user code. Instead it is called as compiler-generated code for those classes and objects (but not traits) that inherit from the DelayedInit trait and that do not themselves define a delayedInit method.

Attributes

body

the initialization code to be stored for later execution

Deprecated
true
Definition Classes
Source:
App.scala

Concrete fields

final val executionStart: Long

The time when the execution of this program started, in milliseconds since 1 January 1970 UTC.

The time when the execution of this program started, in milliseconds since 1 January 1970 UTC.

Attributes

Source:
App.scala