Powershell Design Patterns Command

class Command {

# Declara uma interface para comandos abstratos como Execute().

Execute() {}

}

class Receiver {

# Sabe como executar um comando particular.

SwitchOn() {

Write-Host "Switch on from: " $this.GetType().Name

}

}

class OnCommand: Command {

[Receiver] $Receiver

OnCommand([Receiver] $Receiver) {

$this.Receiver = $Receiver

}

Execute() {

$this.Receiver.SwitchOn()

}

}

class Invoker {

[Command] $Command

Invoker([Command] $Command) {

$this.Command = $Command

}

Execute() {

$this.Command.Execute()

}

}

class TV: Receiver {

[String] toString() {

return $this.GetType().Name

}

}

class DVDPlayer: Receiver {

[String] toString() {

return $this.GetType().Name

}

}

class Main {

Main() {

# Receiver é quem recebe o sabe como realizar o comando.

[Receiver] $Receiver = [TV]::new()

# O Comando do tipo OnCommand recebe o receiver acima.

[Command] $OnCommand = [OnCommand]::new($Receiver)

# O invoker recebe o OnCommand acima, que tem o receiver

[Invoker] $Invoker = [Invoker]::new($OnCommand)

# O comando é chamado pelo Invoker.

$Invoker.Execute()

# On command for DVDPlayer with same invoker

[Receiver] $Receiver = [DVDPlayer]::new()

[Command] $OnCommand = [OnCommand]::new($Receiver)

[Invoker] $Invoker = [Invoker]::new($OnCommand)

$Invoker.Execute()

}

}

[Main]::new()