@startuml
package com.iluwatar.lazy.loading {
  ~class HeavyFactory {
    - heavyInstance : Heavy
    ~ HeavyFactory()
    + get() : Heavy
  }
  class App {
    + App()
    + main(args : String[]) {static}
  }
  class HolderThreadSafe {
    - heavy : Heavy
    + HolderThreadSafe()
    + getHeavy() : Heavy
  }
  class Heavy {
    + Heavy()
  }
  class HolderNaive {
    - heavy : Heavy
    + HolderNaive()
    + getHeavy() : Heavy
  }
  class Java8Holder {
    - heavy : Supplier<Heavy>
    + Java8Holder()
    - createAndCacheHeavy() : Heavy
    + getHeavy() : Heavy
  }
}
HolderNaive -->  "-heavy" Heavy
HolderThreadSafe -->  "-heavy" Heavy
HeavyFactory -->  "-heavyInstance" Heavy
@enduml