Java--设计模式之策略模式

策略模式，又叫算法簇模式，就是定义了不同的算法族，并且之间可以互相替换，此模式让算法的变化独立于使用算法的客户。简而言之就是用一个类来接收实例化对象，从而达到动态改变对象的行为。

通过商场促销来说明，例子如下：

1、基类收费

public interface CashSuper{public int acceptCash(int money);}

2、实现基类--正常收费

public class CashNormal implements CashSuper{@Overridepublic int acceptCash(int money) {return money;}}

3、实现基类--打折收费

public class CashRebate implements CashSuper{private int moneyRebate;public CashRebate(int moneyRebate) {super();this.moneyRebate = moneyRebate;}@Overridepublic int acceptCash(int money) {return money*moneyRebate;}public int getMoneyRebate() {return moneyRebate;}public void setMoneyRebate(int moneyRebate) {this.moneyRebate = moneyRebate;}}

4、实现基类--返利收费

public class CashReturn implements CashSuper{private int moneyCondition;private int moneyReturn;public CashReturn(int moneyCondition, int moneyReturn) {super();this.moneyCondition = moneyCondition;this.moneyReturn = moneyReturn;}@Overridepublic int acceptCash(int money) {int result = money;if(money>moneyCondition){result = money - money/moneyCondition *moneyReturn;}return result;}public int getMoneyCondition() {return moneyCondition;}public void setMoneyCondition(int moneyCondition) {this.moneyCondition = moneyCondition;}public int getMoneyReturn() {return moneyReturn;}public void setMoneyReturn(int moneyReturn) {this.moneyReturn = moneyReturn;}}

5、策略实现类

public class CashContext {private CashSuper cashSuper;public CashContext(CashSuper cashSuper){this.cashSuper = cashSuper;}public int getResult(int money){return cashSuper.acceptCash(money);}}