学习大话设计模式02_工厂模式 进阶至 策略模式

  1 /**
  2  * 现金收费抽象类
  3  * @author Monica
  4  *
  5  */
  6 public abstract class CashSuper {
  7     /**
  8      * 现金收取超类的抽象方法
  9      * @param money 收取现金，参数为原价
 10      * @return 返回当前价
 11      */
 12     public abstract double acceptCash(double money);
 13 }
 14 
 15 /**
 16  * 正常收费子类
 17  * @author Monica
 18  *
 19  */
 20 public class CashNormal extends CashSuper{
 21 
 22     /**
 23      * 正常收费，原价返回
 24      */
 25     @Override
 26     public double acceptCash(double money) {
 27         return money;
 28     }
 29 
 30 }
 31 
 32 /**
 33  * 打折收费子类
 34  * @author Monica
 35  *
 36  */
 37 public class CashRebate extends CashSuper{
 38     private double moneyRebate = 1d;
 39     
 40     public CashRebate(String moneyRebate) {
 41         /*
 42          * 打折收费，初始化时，必须输入折扣费，如八折，就是0.8
 43          */
 44         this.moneyRebate = Double.parseDouble(moneyRebate);
 45     }
 46 
 47     @Override
 48     public double acceptCash(double money) {        
 49         return money * moneyRebate;
 50     }
 51 
 52 }
 53 
 54 /**
 55  * 返回收费子类
 56  * @author Monica
 57  *
 58  */
 59 public class CashReturn extends CashSuper {
 60     //返利条件
 61     private double moneyCondition = 0.0d;
 62     //返利值
 63     private double moneyReturn = 0.0d;
 64 
 65     public CashReturn(String moneyCondition, String moneyReturn) {
 66         this.moneyCondition = Double.parseDouble(moneyCondition);
 67         this.moneyReturn = Double.parseDouble(moneyReturn);
 68     }
 69     
 70     @Override
 71     public double acceptCash(double money) {
 72         double result = money;
 73         if (money >= moneyCondition) {
 74             //若大于返利条件，则需要减去返利值
 75             result = money - Math.floor(money / moneyCondition) * moneyReturn; 
 76         }
 77         return result;
 78     }
 79 }
 80 
 81 /**
 82  * 现金收费工厂类
 83  * @author Monica
 84  *
 85  */
 86 public class CashFactory {
 87     public static CashSuper createCashAccept(String type) {
 88         CashSuper cs = null;
 89         switch (type) {
 90         case "正常收费":
 91             cs = new CashNormal();
 92             break;
 93         case "满300返回100":
 94             cs = new CashReturn("300", "100");
 95             break;
 96         case "打8折":
 97             cs = new CashRebate("0.8");
 98             break;
 99         }
100         return cs;
101     }
102 }

/**
 * 策略与简单工厂结合
 * @author Monica
 *
 */
public class CashContext {
    CashSuper cs = null;
    
    public CashContext(String type) {
        switch (type) {
        case "正常收费":
            cs = new CashNormal();
            break;
        case "满300返回100":
            cs = new CashReturn("300", "100");
            break;
        case "打8折":
            cs = new CashRebate("0.8");
            break;
        }
    }
    
    public double GetResult(double money) {
        return cs.acceptCash(money);
    }
}

//客户端
    public static void main(String[] args) {
        CashContext csuper = new CashContext("打8折");
        double totalPrices = 0d;
        totalPrices = csuper.GetResult(Double.parseDouble("800"));
    }