Strategy pattern implementation in kotlin

README.adoc

Strategy pattern implementation in kotlin (kotlinlang.org) language

Important

make sure to have kotlinc on your $PATH

Running

• Without any command line arguments

  $ kotlinc -script strategy.kts 200
  java.lang.IllegalArgumentException: Invalid speed
          at Strategy.<init>(strategy.kts:9)

• Slow pace town building

  kotlinc -script strategy.kts slow
  
  Building at slow pace...
  
  Town built in 3000 milliseconds!

• Medium pace town building

  kotlinc -script strategy.kts medium
  
  Building at medium pace...
  
  Town built in 1500 milliseconds!

• Fast pace town building

  kotlinc -script strategy.kts fast
  
  Building at fast pace...
  
  Town built in 50 milliseconds!

strategy.kts

class TownBuilder(val buildingStrategy: () -> Long) {
    fun build() {
        val pace = buildingStrategy.invoke()
        Thread.sleep(pace)
        println("Town built in $pace milliseconds!")
    }
}

TownBuilder(
    when(args[0]) {
        "slow" -> { 
            println("\nBuilding at slow pace...\n")
            fun() = 3000L
        }
        "medium" -> {
            println("\nBuilding at medium pace...\n")
            fun() = 1500L
        }
        "fast" -> {
            println("\nBuilding at fast pace...\n")
            fun() = 50L
        }
        else -> throw IllegalArgumentException("Invalid speed")
    }
).build()