学习Head First设计模式Day1

Java设计模式之设计模式

策略模式:策略模式定义了算法簇,分别封装起来,让他们之间可以互相替换,此设计模式让算法的变化独立于使用算法的客户.

全面的想法

一个简单的代码实现:

public abstract class Character {
    WeaponBehaveior weapon;
    abstract void fight();
    public void show(){
        weapon.useWeapon();
    }
    public void setWeapon(WeaponBehaveior wb){
        weapon=wb;
        }
}

声明一个父类

public interface WeaponBehaveior {
    void useWeapon();
}

声明接口

public class KnifeBehavior implements WeaponBehaveior {
    public void useWeapon() {
        System.out.println("use Kinfe fight");
    }

}

public class AxeBehavior implements WeaponBehaveior {
        @Override
    public void useWeapon() {
        System.out.println("use Axe fight");
    }

}

接口的实现类

public class King extends Character {
    private String name;
    public King(String name){
        this.name=name;
        weapon=null;
    }
    @Override
    void fight() {
        System.out.println("I'm fight");
    }

}

父类的子类,继承父类的weapon

public class DesignMode {
        public static void main(String[] args) {
        Character ch=new King("Tom");
        ch.setWeapon(new KnifeBehavior());
        ch.fight();
        ch.show();

    }

}