"😭 미친 남친 탈출!"종속성 주입을 가장 간단한 방법으로 설명

🔥 위험한 상황

class Woman {
  makeLover(){
    const bf = new CrazyMan()
    bf.stayWith()
  }
}

class CrazyMan {
  stayWith() {
    console.log('I am dangerous man, stay with me')
  }
}

const woman = new Woman()
woman.makeLover()

// I am dangerous man, stay with me

👦 좋은남자가 있다!!

class Woman {
  makeLover(){
    const bf = new CrazyMan()
    bf.stayWith()
  }
}

class CrazyMan {
  stayWith() {
    console.log('I am dangerous man, stay with me')
  }
}

// good man !!!!!!!
class GoodMan {
  stayWith() {
    console.log('I am good man, stay with me')
  }
}

const woman = new Woman()
woman.makeLover()

// 😰 But still she stays with dangerous man
// "I am dangerous man, stay with me"

class Woman {
  makeLover(){
    // here, crazy man exists in Woman class, he is aaaaaaalways with her
    const bf = new CrazyMan()
    bf.stayWith()
  }
}

class Woman {
  // She does not depend on crazy man, she has choice now !!
  constructor(man) {
    this.man = man
  }
  makeLover(){
    this.man.stayWith()
  }
}

class CrazyMan {
  stayWith() {
    console.log('I am dangerous man, stay with me')
  }
}

class GoodMan {
  stayWith() {
    console.log('I am good man, stay with me')
  }
}

const man = new GoodMan()
const woman = new Woman(man)
woman.makeLover()

// I am good man, stay with me