1、模式依赖基础与原则

1.1、基础

抽象，封装，多态，继承

1.2、原则

封装变化，多用组合、少用继承，针对接口编程，不针对实现编程

2、策略模式

  策略模式定义了算法族，分别封装起来，让它们之间可以互相替换，此模式让算法的变化独立于使用算法的客户。

2.1、实例：鸭子的行为测试

#抽象类：duck
package com.zhukunshuai.duck.group;
import com.zhukunshuai.duck.flybehavior.FlyBehavior;
import com.zhukunshuai.duck.quackbehavior.QuackBehavior;
public abstract class Duck {
    FlyBehavior flyBehavior;
    QuackBehavior quackBehavior;
    public Duck() {}  //无参构造方法（默认添加，因此可不写）
    public abstract void display();  //抽象方法必须在继承中被重写    
    ##动态设定方法
    public void setFlyBehavior(FlyBehavior fb){ 
        flyBehavior=fb;
    }
    public void setQuackBehavior(QuackBehavior qb){
        quackBehavior=qb;
    }
    public void performFly() {
        flyBehavior.fly();
    }
    public void performQuack() {
        quackBehavior.quack();
    }
    public void swim() {
        System.out.println("All ducks float,even decoys");
    }
}

抽象类设定方法接口：FlyBehavior、QuackBehavior 及其接口实现类

#设定：接口FlyBehavior
package com.zhukunshuai.duck.flybehavior;
public interface FlyBehavior {
    public void fly();
}

#接口FlyBehavior 实现类FlyNoWay 
package com.zhukunshuai.duck.flybehavior;
public class FlyNoWay implements FlyBehavior {
    public void fly(){  //重写接口方法
        System.out.println("I can't fly!!");
    }
}

#接口FlyBehavior 实现类FlyWithWings 
package com.zhukunshuai.duck.flybehavior;
public class FlyWithWings implements FlyBehavior {
    public void fly(){
        System.out.println("I'm flying!!");
    }
}

#设定：接口QuackBehavior 
package com.zhukunshuai.duck.quackbehavior;
public interface QuackBehavior {
    public void quack();
}

#接口QuackBehavior 实现类Quack 
package com.zhukunshuai.duck.quackbehavior;
public class Quack implements QuackBehavior {
    public void quack() {
        System.out.println("Quack");
    }
}

#接口QuackBehavior 实现类Squeak 
package com.zhukunshuai.duck.quackbehavior;
public class Squeak implements QuackBehavior {
    public void quack() {
        System.out.println("Squeak");
    }
}

ModelDuck、MallardDuck继承duck类

package com.zhukunshuai.duck.group;
import com.zhukunshuai.duck.flybehavior.FlyNoWay;
import com.zhukunshuai.duck.quackbehavior.Quack;
public class ModelDuck extends Duck {
    public ModelDuck(){ 
        flyBehavior=new FlyNoWay();
        quackBehavior=new Quack();
    }
    public void display(){ //重写抽象方法
        System.out.println("I'm a model duck!!");
    }
}

package com.zhukunshuai.duck.group;
import com.zhukunshuai.duck.flybehavior.FlyNoWay;
import com.zhukunshuai.duck.quackbehavior.MuteQuack;
public class MallardDuck extends Duck {
    public MallardDuck() {
        quackBehavior = new Squeak();
        flyBehavior = new FlyWithWings();
    }
    public void display() {
        System.out.println("I'm a real Mallard duck!!");
    }
}

测试实例

package com.zhukunshuai.duck;
import com.zhukunshuai.duck.flybehavior.FlyNoWay;
import com.zhukunshuai.duck.group.Duck;
import com.zhukunshuai.duck.group.ModelDuck;

import com.zhukunshuai.duck.quackbehavior.Quack;
import com.zhukunshuai.duck.quackbehavior.QuackBehavior;
public class miniDuck {
    public static void main(String[] args) {

        /*Duck mallard = new MallardDuck();
        mallard.performFly();
        mallard.performQuack();
        mallard.swim();*/
        
        Duck model=new ModelDuck();
        model.performFly();    //输出：I'm flying!!
        model.performQuack();   //输出：Squeak
        model.setFlyBehavior(new FlyNoWay());
        QuackBehavior quack = new Quack();
        model.setQuackBehavior(quack);
        model.performFly();   //输出：I can't fly!!
        model.performQuack();  //输出：Quack
    }
}

输出结果：

    I'm flying!!
    Squeak
    I can't fly!!
    Quack

2.2、实例：chess中

package com.zhukunshuai.chess.role;
import com.zhukunshuai.chess.weapon.WeaponBehavior;
public abstract class Role {
    WeaponBehavior weaponBehavior;
    public Role() {}
    public abstract void display();
    public void setWeapon(WeaponBehavior weapon) {
        weaponBehavior = weapon;
    }
    public void performweapon() {
        weaponBehavior.useweapon();
    }
    public void getname() {
        System.out.println("this is chess!!");
    }
}

package com.zhukunshuai.chess.role;
import com.zhukunshuai.chess.weapon.BowAndArrowBehavior;
public class Queen extends Role{
    public Queen(){
        weaponBehavior=new BowAndArrowBehavior();
    }
    public void display(){
        System.out.println("I am queen");
    }   
}

package com.zhukunshuai.chess.role;
import com.zhukunshuai.chess.weapon.AxeBehavior;
public class King extends Role{
    public King(){
         weaponBehavior=new AxeBehavior();
    }
    public void display(){
        System.out.println("I am King");
    }
}

package com.zhukunshuai.chess.weapon;
public interface WeaponBehavior {
    public void useweapon();
}

package com.zhukunshuai.chess.weapon;
public class AxeBehavior implements WeaponBehavior {
    public void useweapon(){
        System.out.println("使用斧子");
    }
}

package com.zhukunshuai.chess.weapon;
public class BowAndArrowBehavior implements WeaponBehavior {
    public void useweapon(){
        System.out.println("使用弓箭");
    }
}

测试实例

package com.zhukunshuai.chess;
import com.zhukunshuai.chess.role.King;
import com.zhukunshuai.chess.role.Role;
import com.zhukunshuai.chess.weapon.SwordBehavior;
public class strange {
    public static void main(String[] args) {
        Role member=new King();
        member.display();
        member.getname();
        member.performweapon();
        member.setWeapon(new BowAndArrowBehavior());
        member.performweapon();
    }
}

输出结果：

    I am King
    this is chess!!
    使用斧子
    使用弓箭

3、观察者模式

4、装饰者模式

5、工厂模式