工厂模式

工厂模式

let Basketball = function () {
  this.name = 'basketball'
}
Basketball.prototype = {
  getMember: function () {
    console.log(5)
  },
  getBallSize: function () {
    console.log('big')
  },
}

let FootBall = function () {
  this.name = 'football'
}
FootBall.prototype = {
  getMember: function () {
    console.log(11)
  },
  getBallSize: function () {
    console.log('big')
  },
}

let Tennis = function () {
  this.name = 'tennis'
}
Tennis.prototype = {
  getMember: function () {
    console.log(1)
  },
  getBallSize: function () {
    console.log('small')
  },
}

let SportFactory = function (name) {
  switch (name) {
    case 'basketball':
      return new Basketball()
    case 'football':
      return new FootBall()
    case 'tennis':
      return new Tennis()
  }
}

let footBall = new SportFactory('football')
footBall.getMember()

// Product base attribute
interface Product {
  operation(): string
}

class ConcreteProduct1 implements Product {
  public operation(): string {
    return 'This is Product1'
  }
}
class ConcreteProduct2 implements Product {
  public operation(): string {
    return 'This is Product2'
  }
}

abstract class Creator {
  public abstract factoryMethod(): Product

  public operation(): string {
    const product = this.factoryMethod()

    return product.operation()
  }
}

class ConcreteCreator1 extends Creator {
  public factoryMethod(): Product {
    return new ConcreteProduct1()
  }
}
class ConcreteCreator2 extends Creator {
  public factoryMethod(): Product {
    return new ConcreteProduct2()
  }
}

// usage
function clientCode(creator: Creator) {
  console.log(creator.operation())
}

clientCode(new ConcreteCreator1())
clientCode(new ConcreteCreator2())

安全工厂

let Factory = function (type, content) {
  if (this instanceof Factory) {
    // check if is instance Factory
    return new this[type](content)
  } else {
    return new Factory(type, content)
  }
}
Factory.prototype = {
  Java: function (content) {
    console.log(content)
  },
  JavaScript: function (content) {
    console.log(content)
  },
}

let data = [
  {
    type: 'Java',
    content: 'This is Java',
  },
  {
    type: 'JavaScript',
    content: 'This is JavaScript',
  },
]

// for test
for (let i = 0; i < data.length; i++) Factory(data[i].type, data[i].content)

抽象工厂

/**
 * to extend superType
 * @param {*} subType
 * @param {*} superType
 */
let VehicleFactory = (subType, superType) => {
  if (typeof VehicleFactory[superType] === 'function') {
    function F() {}
    F.prototype = new VehicleFactory[superType]()
    subType.constuctor = subType
    subType.prototype = new F()
  } else {
    throw new Error("don' not have this abstract class")
  }
}

// create base class
VehicleFactory.Car = function () {
  this.type = 'car'
}
VehicleFactory.Car.prototype = {
  getPrice: function () {
    return new Error('abstract')
  },
  getSpeed: function () {
    return new Error('abstract')
  },
}

let BMW = function (price, speed) {
  this.price = price
  this.speed = speed
}
VehicleFactory(BMW, 'Car') // interface
BMW.prototype = {
  getPrice: function () {
    return this.price
  },
  getSpeed: function () {
    return this.speed
  },
}

// for test
let myBmw = new BMW(10000, 100)
console.log(myBmw.getPrice())

// product interface
interface AbstractProductA {
  functionA(): string
}

interface AbstractProductB {
  /**
   * base operation
   * @return {string}
   */
  functionA(): string

  /**
   * inject some operation
   * @param {AbstractProductA} product
   * @return {string}
   */
  functionB(product: AbstractProductA): string
}

// concrete production
class ConcreteProductA1 implements AbstractProductA {
  functionA(): string {
    return 'This is functionA from ProductA1'
  }
}
class ConcreteProductA2 implements AbstractProductA {
  functionA(): string {
    return 'This is functionA from ProductA2'
  }
}
class ConcreteProductB1 implements AbstractProductB {
  functionA(): string {
    return 'This is functionA from ProductB1'
  }

  functionB(product: AbstractProductA): string {
    return 'Function B2: ' + product.functionA()
  }
}
class ConcreteProductB2 implements AbstractProductB {
  functionA(): string {
    return 'This is functionA from ProductB2'
  }

  functionB(product: AbstractProductA): string {
    return 'Function B2: ' + product.functionA()
  }
}

// factory interface
interface AbstractFactory {
  createProductA(): AbstractProductA
  createProductB(): AbstractProductB
}

// concrete factory
class ConcreteFactory1 implements AbstractFactory {
  createProductA(): AbstractProductA {
    return new ConcreteProductA1()
  }

  createProductB(): AbstractProductB {
    return new ConcreteProductB1()
  }
}
class ConcreteFactory2 implements AbstractFactory {
  createProductA(): AbstractProductA {
    return new ConcreteProductA2()
  }

  createProductB(): AbstractProductB {
    return new ConcreteProductB2()
  }
}

// usage
/**
 * use with different facotry.
 * @param {AbstractFactory} factory
 */
function clientCode(factory: AbstractFactory) {
  const productA = factory.createProductA()
  const productB = factory.createProductB()

  console.log(productB.functionA())
  console.log(productB.functionB(productA))
}

clientCode(new ConcreteFactory1())
clientCode(new ConcreteFactory2())