简单工厂模式

披萨项目：要方便披萨品种的扩展、要便于维护、要能运行时扩展

简单工厂模式的设计方案：定义一个实例化披萨对象的类，封装创建对象的代码

简单工厂模式：定义了一个创建对象的类，由这个类来封装实例化对象的行为

代码如下：

package com.java.jikexueyuan.pizzastore.simplefactory;

import com.java.jikexueyuan.pizzastore.pizza.CheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.GreekPizza;
import com.java.jikexueyuan.pizzastore.pizza.PepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public class SimplePizzaFactory {

public Pizza CreatePizza(String ordertype) {
Pizza pizza = null;

if (ordertype.equals("cheese")) {
pizza = new CheesePizza();
} else if (ordertype.equals("greek")) {
pizza = new GreekPizza();
} else if (ordertype.equals("pepper")) {
pizza = new PepperPizza();
}
return pizza;

}

}

package com.java.jikexueyuan.pizzastore.pizza;

public abstract class Pizza {
protected String name;

public abstract void prepare();
public void bake()
{
System.out.println(name+" baking;");
}
public void cut()
{
System.out.println(name+" cutting;");
}
public void box()
{
System.out.println(name+" boxing;");
}
public void setname(String name)
{
this.name=name;
}
}

package com.java.jikexueyuan.pizzastore.pizza;

public class CheesePizza extends Pizza {

@Override
public void prepare() {
// TODO Auto-generated method stub
super.setname("CheesePizza");

System.out.println(name+" preparing;");
}

}

package com.java.jikexueyuan.pizzastore.simplefactory;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import com.java.jikexueyuan.pizzastore.pizza.CheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.GreekPizza;
import com.java.jikexueyuan.pizzastore.pizza.PepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public class OrderPizza {
SimplePizzaFactory mSimplePizzaFactory;

public OrderPizza(SimplePizzaFactory mSimplePizzaFactory) {

setFactory(mSimplePizzaFactory);
}

public void setFactory(SimplePizzaFactory mSimplePizzaFactory) {
Pizza pizza = null;
String ordertype;

this.mSimplePizzaFactory = mSimplePizzaFactory;

do {
ordertype = gettype();
pizza = mSimplePizzaFactory.CreatePizza(ordertype);
if (pizza != null) {
pizza.prepare();
pizza.bake();
pizza.cut();
pizza.box();
}

} while (true);

}

private String gettype() {
try {
BufferedReader strin = new BufferedReader(new InputStreamReader(
System.in));
System.out.println("input pizza type:");
String str = strin.readLine();

return str;
} catch (IOException e) {
e.printStackTrace();
return "";
}
}

}

工厂方法模式

披萨项目加盟店

工厂方法模式设计方案：将披萨项目里的披萨对象实例化功能抽象成抽象方法，在不同加盟店具体实现功能。

工厂方法模式：定义了一个创建对象的抽象方法，由子类决定要实例化的类。 工厂方法模式将对象的实例化推迟到子类

代码如下

package com.java.jikexueyuan.pizzastore.method;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import com.java.jikexueyuan.pizzastore.pizza.CheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.ChinesePizza;
import com.java.jikexueyuan.pizzastore.pizza.GreekPizza;
import com.java.jikexueyuan.pizzastore.pizza.PepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public abstract class OrderPizza {

public OrderPizza() {
Pizza pizza = null;
String ordertype;

do {
ordertype = gettype();
pizza = createPizza(ordertype);

pizza.prepare();
pizza.bake();
pizza.cut();
pizza.box();
} while (true);
}

abstract Pizza createPizza(String ordertype);

private String gettype() {
try {
BufferedReader strin = new BufferedReader(new InputStreamReader(
System.in));
System.out.println("input pizza type:");
String str = strin.readLine();

return str;
} catch (IOException e) {
e.printStackTrace();
return "";
}
}

}

package com.java.jikexueyuan.pizzastore.method;

import com.java.jikexueyuan.pizzastore.pizza.CheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.GreekPizza;
import com.java.jikexueyuan.pizzastore.pizza.NYCheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.NYPepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.PepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public class NYOrderPizza extends OrderPizza {

@Override
Pizza createPizza(String ordertype) {
Pizza pizza = null;

if (ordertype.equals("cheese")) {
pizza = new NYCheesePizza();
} else if (ordertype.equals("pepper")) {
pizza = new NYPepperPizza();
}
return pizza;

}

}

package com.java.jikexueyuan.pizzastore.method;

import com.java.jikexueyuan.pizzastore.pizza.CheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.GreekPizza;
import com.java.jikexueyuan.pizzastore.pizza.LDCheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.LDPepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.PepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public class LDOrderPizza extends OrderPizza {

@Override
Pizza createPizza(String ordertype) {
Pizza pizza = null;

if (ordertype.equals("cheese")) {
pizza = new LDCheesePizza();
} else if (ordertype.equals("pepper")) {
pizza = new LDPepperPizza();
}
return pizza;

}

}

抽象工厂模式

抽象工厂模式：定义了一个接口用于创建相关或有依赖关系的对象族，而无需明确指定具体类

package com.java.jikexueyuan.pizzastore.absfactory;

import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public interface AbsFactory {
public Pizza CreatePizza(String ordertype) ;
}

package com.java.jikexueyuan.pizzastore.absfactory;

import com.java.jikexueyuan.pizzastore.pizza.LDCheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.LDPepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public class LDFactory implements AbsFactory {
@Override
public Pizza CreatePizza(String ordertype) {
Pizza pizza = null;

if (ordertype.equals("cheese")) {
pizza = new LDCheesePizza();
} else if (ordertype.equals("pepper")) {
pizza = new LDPepperPizza();
}
return pizza;
}
}

package com.java.jikexueyuan.pizzastore.absfactory;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import com.java.jikexueyuan.pizzastore.pizza.CheesePizza;
import com.java.jikexueyuan.pizzastore.pizza.GreekPizza;
import com.java.jikexueyuan.pizzastore.pizza.PepperPizza;
import com.java.jikexueyuan.pizzastore.pizza.Pizza;

public class OrderPizza {
AbsFactory mFactory;

public OrderPizza(AbsFactory mFactory) {

setFactory(mFactory);
}

public void setFactory(AbsFactory mFactory) {
Pizza pizza = null;
String ordertype;

this.mFactory = mFactory;

do {
ordertype = gettype();
pizza = mFactory.CreatePizza(ordertype);
if (pizza != null) {
pizza.prepare();
pizza.bake();
pizza.cut();
pizza.box();
}

} while (true);

}

private String gettype() {
try {
BufferedReader strin = new BufferedReader(new InputStreamReader(
System.in));
System.out.println("input pizza type:");
String str = strin.readLine();

return str;
} catch (IOException e) {
e.printStackTrace();
return "";
}
}

}

依赖抽象原则

　　变量不要持有具体类的引用

　　不要让类继承自具体类，要继承自抽象类或接口　

　　不要覆盖基类中已实现的方法