02 工厂模式

举例制造Pizza的工厂

简单工厂模式(一般用这种就可以了)

　　工厂类里, 通过 if else 来创建不同的具体类. 多个品牌只有一个工厂，通过 if else 来判断制造什么样的Pizza(海鲜Pizza, 榴莲Pizza)

　　

package com.leon.design;

public class SimpleFactory {

    public static void main(String[] args) {
        PizzaFactory factory = new PizzaFactory();
        Pizza p1 = factory.CreatePizza("Cheese");
        Pizza p2 = factory.CreatePizza("Greek");
        p1.prepare();
        p1.bake();
        p2.prepare();
        p2.bake();
    }
}

abstract class Pizza {
    protected String name;
    //抽象方法, 因为不同的pizza, 准备的方法不一样, 所以需要继承自己去实现
    public abstract void prepare();
    public void bake() {
        System.out.println(name + " fire baking");
    }
    public void cut() {
        System.out.println(name + " knife cutting");
    }
    public void box() {
        System.out.println(name + " people boxing");
    }
    public void setName(String name) {
        this.name = name;
    }
}

class CheesePizza extends Pizza {
    @Override
    public void prepare() {
        System.out.println(name + " preapare: put cheese into pizza");    
    }
}
class GreekPizza extends Pizza {
    @Override
    public void prepare() {
        System.out.println(name + " preapare: put greek into pizza");    
    }
}
class PizzaFactory {
    public Pizza CreatePizza(String s) {
        if (s.equals("Cheese")) {
            return new CheesePizza();
        } else if (s.equals("Greek")) {
            return new GreekPizza();
        }
        return null;
    }
}

工厂模式: 每个品牌有自己的制造工厂

package com.leon.design;

public class StandardFactory {

    public static void main(String[] args) {
        CheesePizzaFactory cheeseFactory = new CheesePizzaFactory();
        GreekPizzaFactory greekFactory = new GreekPizzaFactory();
        Pizza p1 = cheeseFactory.CreatePizza();
        Pizza p2 = greekFactory.CreatePizza();
        p1.prepare();
        p1.bake();
        p2.prepare();
        p2.bake();
    }
}

abstract class Pizza {
    protected String name;
    //抽象方法, 因为不同的pizza, 准备的方法不一样, 所以需要继承自己去实现
    public abstract void prepare();
    public void bake() {
        System.out.println(name + " fire baking");
    }
    public void cut() {
        System.out.println(name + " knife cutting");
    }
    public void box() {
        System.out.println(name + " people boxing");
    }
    public void setName(String name) {
        this.name = name;
    }
}

class CheesePizza extends Pizza {
    @Override
    public void prepare() {
        System.out.println(name + " preapare: put cheese into pizza");    
    }
}
class GreekPizza extends Pizza {
    @Override
    public void prepare() {
        System.out.println(name + " preapare: put greek into pizza");    
    }
}
class CheesePizzaFactory {
    public Pizza CreatePizza() {
        return new CheesePizza();
    }
}
class GreekPizzaFactory {
    public Pizza CreatePizza() {
        return new GreekPizza();
    }
}

抽象工厂模式

　　定义了一个interface 用于创建相关或有依赖关系的对象族, 而无需指明具体的类.

　　简单工厂 + 工厂方法 的结合, 抽象工厂 + 具体实现的工厂子类

　　把工厂和产品都要做一个抽象.

　　

package com.leon.design;

public class AbstractFactory {
    public static void main(String[] args) {
        IPizzaFactory factory1 = new CheesePizzaFactory();
        IPizzaFactory factory2 = new GreekPizzaFactory();
        Pizza p1 = factory1.createPizza();
        Pizza p2 = factory2.createPizza();
        p1.prepare();
        p1.bake();
        p2.prepare();
        p2.bake();
    }
}
abstract class Pizza {
    protected String name;
    //抽象方法, 因为不同的pizza, 准备的方法不一样, 所以需要继承自己去实现
    public abstract void prepare();
    public void bake() {
        System.out.println(name + " fire baking");
    }
    public void cut() {
        System.out.println(name + " knife cutting");
    }
    public void box() {
        System.out.println(name + " people boxing");
    }
    public void setName(String name) {
        this.name = name;
    }
}
class CheesePizza extends Pizza {
    @Override
    public void prepare() {
        System.out.println(name + " preapare: put cheese into pizza");    
    }
}
class GreekPizza extends Pizza {
    @Override
    public void prepare() {
        System.out.println(name + " preapare: put greek into pizza");    
    }
}
interface IPizzaFactory{
    public Pizza createPizza();
}
class CheesePizzaFactory implements IPizzaFactory {
    @Override
    public Pizza createPizza() {    
        return new CheesePizza();
    }
    
}
class GreekPizzaFactory implements IPizzaFactory {
    @Override
    public Pizza createPizza() {    
        return new GreekPizza();
    }
}