酷应用

漫画：星球入侵之策略模式

百家作者：程序人生 2019-11-20 10:46:42

作者 |?小小小咖

本文经授权转载自JAVA小咖秀（ID：javaxiaokashow）

比基盗星球还有2万公里将要到达我星球入侵。。。

此时的why星球

public?class?SimpleHero?{

????public?void?fight?(String condition) {
????????if?(condition ==?null?) {
????????????return;
????????}
????????if?("AgainstTheWind".equals(condition)) {
????????????System.out.println("逆风翻盘策略");

????????} else?if?("DownwindSuppression".equals(condition)) {
????????????System.out.println("顺风压制策略");

????????} else?if?("BalanceInPower".equals(condition)) {
????????????System.out.println("势均力敌策略");

????????}
????}

????public?static?void?main(String[] args) {
????????SimpleHero simpleHero = new?SimpleHero();
????????simpleHero.fight("AgainstTheWind");
????}
}

策略模式:定义一些算法族，分别封装，让他们可以相互替换，此模式让算法的变化独立于使用算法的客户。该设计模式属于行为型模式。

策略模式UML图:

public?interface?Strategy?{

????public?void?fight();
}

public?class?AgainstTheWindStrategy?implements?Strategy?{

????@Override
????public?void?fight()?{
????????System.out.println("逆风翻盘策略");
????}
}


public?class?BalanceInPowerStrategy?implements?Strategy?{

????@Override
????public?void?fight()?{
????????System.out.println("势均力敌策略");
????}
}


public?class?DownwindSuppressionStrategy?implements?Strategy?{

????@Override
????public?void?fight()?{
????????System.out.println("顺风压制策略");
????}
}


public?class?Hero?{

????private?Strategy strategy;

????public?Hero(Strategy strategy)?{
????????this.strategy = strategy;
????}

????public?void?useStrategem()?{
????????strategy.fight();
????}

}


public?class?Battlegroud?{

????public?static?void?main(String[] args)?{
????????Hero hero = new?Hero(new?AgainstTheWindStrategy());
????????hero.useStrategem();

????????Hero hero1 = new?Hero(new?BalanceInPowerStrategy());
????????hero1.useStrategem();

????????Hero hero2 = new?Hero(new?DownwindSuppressionStrategy());
????????hero2.useStrategem();

????}
}