@startuml
package com.iluwatar.ruleengine {
  interface Rule<T> {
    + name() : String {abstract}
    + evaluate(context : T) : boolean {abstract}
    + execute(context : T) : void {abstract}
  }
  class RuleEngine<T> {
    - rules : List<Rule<T>>
    + RuleEngine(rules : List<Rule<T>>)
    + run(context : T) : RuleEngineResult
    + rules() : List<Rule<T>>
  }
  class RuleEngineResult {
    + RuleEngineResult(approved : boolean, passedRules : List<String>, failedRules : List<String>)
    + approved() : boolean
    + passedRules() : List<String>
    + failedRules() : List<String>
  }
  class LoanApplication {
    + LoanApplication(age : int, monthlyIncome : double, loanAmount : double, creditScore : int)
    + age() : int
    + monthlyIncome() : double
    + loanAmount() : double
    + creditScore() : int
  }
  class MinimumAgeRule {
    - minimumAge : int
    + MinimumAgeRule(minimumAge : int)
    + name() : String
    + evaluate(context : LoanApplication) : boolean
    + execute(context : LoanApplication) : void
  }
  class MinimumIncomeRule {
    - minimumIncome : double
    + MinimumIncomeRule(minimumIncome : double)
    + name() : String
    + evaluate(context : LoanApplication) : boolean
    + execute(context : LoanApplication) : void
  }
  class CreditScoreRule {
    - minimumScore : int
    + CreditScoreRule(minimumScore : int)
    + name() : String
    + evaluate(context : LoanApplication) : boolean
    + execute(context : LoanApplication) : void
  }
  class App {
    + App()
    + main(args : String[]) : void
  }
}
RuleEngine --> "*" Rule
RuleEngine ..> RuleEngineResult
MinimumAgeRule ..|> Rule
MinimumIncomeRule ..|> Rule
CreditScoreRule ..|> Rule
MinimumAgeRule ..> LoanApplication
MinimumIncomeRule ..> LoanApplication
CreditScoreRule ..> LoanApplication
@enduml