Factory（工厂模式）与Factory Method（工厂方法模式）

工厂系列介绍

• 简单工厂
• 静态工厂
• 工厂方法
• 抽象工厂
• SpringIOC

定义

• 任何可以生产对象的方法或类，都可以称之为工厂
• 单例也是一种工厂
• 不可咬文嚼字，死扣概念
• 为什么有了new之后，还会有工厂?
  • 灵活控制生产过程
  • 权限、修饰、日志。。。

举例

• 任意定制交通工具
• 任意定制生产过程
• 任意定制产品一族

简单的工厂模式（可扩展性不高）

package factory;

/**
 * 简单工厂的可扩展性不好
 */
public class SimpleVehicleFactory {

    public Car createCar(){
        return new Car();
    }

    public Broom createBroom(){
        return new Broom();
    }
}

package factory;

public class CarFactory {
    public Car create(){
        return new Car();
    }
}

package factory;

public class Car {
    public void go() {
        System.out.println("a car created!");
    }
}

package factory;

public class Broom {
    public void go() {
        System.out.println("a Broom created!");
    }
}

package factory;

public class Main {
    public static void main(String[] args) {
        Car car = new CarFactory().create();
        Broom broom = new SimpleVehicleFactory().createBroom();
        car = new SimpleVehicleFactory().createCar();
        car.go();
    }
}

抽象工厂设计

package abstractfactory;

public abstract class AbstractFactory {
    abstract Food createFood();
    abstract Vehicle createVehicle();
    abstract  Weapon createWeapon();
}

package abstractfactory;
public class MagicFactory extends AbstractFactory {
    @Override
    Food createFood() {
        return new MushRoom();
    }

    @Override
    Vehicle createVehicle() {
        return new Broom();
    }

    @Override
    Weapon createWeapon() {
        return new MagicStick();
    }
}

package abstractfactory;
public class ModernFactory extends AbstractFactory {
    @Override
    Food createFood() {
        return new Bread();
    }

    @Override
    Vehicle createVehicle() {
        return new Car();
    }

    @Override
    Weapon createWeapon() {
        return new AK47();
    }
}

package abstractfactory;
public abstract class Food {
    abstract void food();
}

package abstractfactory;
public abstract class Vehicle {
    abstract void go();
}

package abstractfactory;
public abstract class Weapon {
    abstract void shoot();
}

package abstractfactory;
public class AK47 extends Weapon{
    @Override
    public void shoot(){
        System.out.println("tutututu.............");
    }
}

package abstractfactory;
public class Bread extends Food{
    @Override
    void food() {
        System.out.println("wdm");
    }
}

package abstractfactory;
public class Broom extends Vehicle{
    @Override
    public void go() {
        System.out.println("a car Broom!");
    }
}

package abstractfactory;
public class Car extends Vehicle{
    @Override
    public void go() {
        System.out.println("a car created!");
    }
}

package abstractfactory;
public class MagicStick extends Weapon {
    @Override
    public void shoot(){
        System.out.println("diandian.................");
    }
}

package abstractfactory;
public class MushRoom extends Food{
    @Override
    public void food(){
        System.out.println("dmg");
    }
}