@startuml
package com.iluwatar.module {
  class App {
    + consoleLoggerModule : ConsoleLoggerModule {static}
    + fileLoggerModule : FileLoggerModule {static}
    - App()
    + execute(args : String[]) {static}
    + main(args : String[]) {static}
    + prepare() {static}
    + unprepare() {static}
  }
  class ConsoleLoggerModule {
    - LOGGER : Logger {static}
    + error : PrintStream
    + output : PrintStream
    - singleton : ConsoleLoggerModule {static}
    - ConsoleLoggerModule()
    + getSingleton() : ConsoleLoggerModule {static}
    + prepare()
    + printErrorString(value : String)
    + printString(value : String)
    + unprepare()
  }
  class FileLoggerModule {
    - ERROR_FILE : String {static}
    - LOGGER : Logger {static}
    - OUTPUT_FILE : String {static}
    + error : PrintStream
    + output : PrintStream
    - singleton : FileLoggerModule {static}
    - FileLoggerModule()
    + getSingleton() : FileLoggerModule {static}
    + prepare()
    + printErrorString(value : String)
    + printString(value : String)
    + unprepare()
  }
}
FileLoggerModule -->  "-singleton" FileLoggerModule
App -->  "-consoleLoggerModule" ConsoleLoggerModule
ConsoleLoggerModule -->  "-singleton" ConsoleLoggerModule
App -->  "-fileLoggerModule" FileLoggerModule
@enduml