@startuml
package com.iluwatar.strategy {
  class DragonSlayer {
    - strategy : DragonSlayingStrategy
    + DragonSlayer(strategy : DragonSlayingStrategy)
    + changeStrategy(strategy : DragonSlayingStrategy)
    + goToBattle()
  }
  class SpellStrategy {
    + SpellStrategy()
    + execute()
  }
  class ProjectileStrategy {
    + ProjectileStrategy()
    + execute()
  }
  interface DragonSlayingStrategy {
    + execute() {abstract}
  }
  class MeleeStrategy {
    + MeleeStrategy()
    + execute()
  }
  class App {
    + App()
    + main(args : String[]) {static}
  }
}
DragonSlayer -->  "-strategy" DragonSlayingStrategy
SpellStrategy ..|> DragonSlayingStrategy 
ProjectileStrategy ..|> DragonSlayingStrategy 
MeleeStrategy ..|> DragonSlayingStrategy 
@enduml