策略模式和Spring的结合在项目中的应用

来源：互联网发布：中日海军对比2017知乎编辑：程序博客网时间：2024/05/21 07:49

一、策略模式

策略模式的定义：

策略模式是对算法的封装，把使用算法的责任和算法本身分隔开，委派给不同的对象管理。策略模式通常把一系列的算法包装到一系列的策略类里面，作为一个抽象策略类的子类。

这里写图片描述

二、解决了我的什么问题？

在实际的项目中，完成一项任务，可以有多种不同的方式，对于新手来说我们是怎么来用的，很经典的 if…else if…else…，正如下面的这段代码，每一个平台都有自己的HuiTieTicketNumber

if (vendeeId==1){   //携程        TicketContext ticketContextCtrip=CtripTicketContext(reportDetail,orderDetail);        if (ticketContextCtrip!=null){            huitiePiaoHao=new CtripHuiTieTicketNumber();            huitiePiaoHao.handle(ticketContextCtrip);        }    }else if (vendeeId==2){  //去哪        TicketContext ticketContextQunar=QunarTicketContext(reportDetail,orderDetail);        if (ticketContextQunar!=null){            huitiePiaoHao=new QunarHuiTieTicketNumber();            huitiePiaoHao.handle(ticketContextQunar);        }    }else if (vendeeId==3){  //阿里        TicketContext ticketContextQua=QuaTicketContext(reportDetail,orderDetail);        if (ticketContextQua!=null){            huitiePiaoHao=new QuaHuiTieTicketNumber();            huitiePiaoHao.handle(ticketContextQua);        }    }else if (vendeeId==4){  //同程        TicketContext ticketContextTongCheng=QunarTicketContext(reportDetail,orderDetail);        if (ticketContextTongCheng!=null){            huitiePiaoHao=new TongChengHuiTieTicketNumber();            TicketContext ticketContext=huitiePiaoHao.handle(ticketContextTongCheng);            if (ticketContext.getStatus()==2){            }        }    }}

当然，如果只是为了完成功能，这样做确实是可行的，但是，这样也会被局限住，如果新增一个平台呢，就需要再来修改代码，这就违背了对内修改关闭，对外扩展开放的原则。所以在这个地方应用了策略模式。把每一个平台的HuiTie当成一种策略封装到独立的类中进行处理。

三、代码实现

策略工厂类，具体的策略类是在spring注入的。

/** * 平台策略模式工厂类 * Created by ling.zhang on 2017/1/21. */public class OrderIntegrateReadFactory {    private final static Logger logger= LoggerFactory.getLogger(OrderIntegrateReadFactory.class);    private Map<String,IVendeeContextStrategy> vendeeContextStrategyMap=new HashMap<String, IVendeeContextStrategy>();    public Map<String, IVendeeContextStrategy> getVendeeContextStrategyMap() {        return vendeeContextStrategyMap;    }    public void setVendeeContextStrategyMap(Map<String, IVendeeContextStrategy> vendeeContextStrategyMap) {        this.vendeeContextStrategyMap = vendeeContextStrategyMap;    }    public boolean doAction(String strType, ReportDetail reportDetail, OrderDetail orderDetail){        return this.vendeeContextStrategyMap.get(strType).getTicketContext(reportDetail,orderDetail);    }}

spring配置文件

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"       xmlns:context="http://www.springframework.org/schema/context"       xsi:schemaLocation="http://www.springframework.org/schema/beans  http://www.springframework.org/schema/beans/spring-beans-3.1.xsd  http://www.springframework.org/schema/context  http://www.springframework.org/schema/context/spring-context-3.2.xsd">    <bean id="orderIntegrateReadFactory" class="com.flight.inter.otaadapter.factory.OrderIntegrateReadFactory">       <property name="vendeeContextStrategyMap">           <map>               <entry key="1" value-ref="ctripContextStrategy"/>               <entry key="2" value-ref="qunarContextStrategy"/>               <entry key="3" value-ref="aliquaContextStrategy"/>               <entry key="4" value-ref="tongChengContextStrategy"/>           </map>       </property>    </bean>    <bean id="ctripContextStrategy" class="com.flight.inter.otaadapter.manage.cloudticket.CtripContextStrategy">        <property name="huitiePiaoHao" ref="ctripHuiTieTicketNumber"/>        <property name="redisManage" ref="policyRedis"/>    </bean>    <bean id="qunarContextStrategy" class="com.flight.inter.otaadapter.manage.cloudticket.QunarContextStrategy">        <property name="huitiePiaoHao" ref="qunarHuiTieTicketNumber"/>        <property name="redisManage" ref="policyRedis"/>    </bean>    <bean id="aliquaContextStrategy" class="com.flight.inter.otaadapter.manage.cloudticket.AliquaContextStrategy">        <property name="huitiePiaoHao" ref="quaHuiTieTicketNumber"/>        <property name="redisManage" ref="policyRedis"/>    </bean>    <bean id="tongChengContextStrategy" class="com.flight.inter.otaadapter.manage.cloudticket.TongChengContextStrategy">        <property name="huitiePiaoHao" ref="TongChengHuiTieTicketNumber"/>        <property name="redisManage" ref="policyRedis"/>    </bean></beans>

接口类：

/** * Created by ling.zhang on 2017/1/21. */public interface IVendeeContextStrategy {    boolean getTicketContext(ReportDetail reportDetail, OrderDetail orderDetail);}

具体的实现类：

public class QunarContextStrategy implements IVendeeContextStrategy{    private final static Logger logger= LoggerFactory.getLogger(QunarContextStrategy.class);    HandleManage<TicketContext> huitiePiaoHao;    RedisManager redisManage;    public RedisManager getRedisManage() {        return redisManage;    }    public void setRedisManage(RedisManager redisManage) {        this.redisManage = redisManage;    }    public HandleManage<TicketContext> getHuitiePiaoHao() {        return huitiePiaoHao;    }    public void setHuitiePiaoHao(HandleManage<TicketContext> huitiePiaoHao) {        this.huitiePiaoHao = huitiePiaoHao;    }    @Override    public boolean getTicketContext(ReportDetail reportDetail, OrderDetail orderDetail){       try {           TicketContext ticketContextQunar = QunarTicketContext(reportDetail, orderDetail);           if (ticketContextQunar != null) {               TicketContext ticketContext=huitiePiaoHao.handle(ticketContextQunar);               if (ticketContext.isHuitieresult()){                   redisManage.add("vendee-"+ticketContext.getTtsorderno(),"true");                   redisManage.expire("vendee-"+ticketContext.getTtsorderno(),600);                   logger.info("orderintegrate huitie success data {}",JSONObject.toJSONString(ticketContext));                   return true;               }           }       }catch (Exception e){           logger.error("orerintegrate read ticketcontext error {}",e);            return false;       }        return false;    } }

每个平台都会有上面的这个Strategy类，就不一一列举了。这样的话，当你的需求中在来一个新的平台的时候，只需要新建一个类，并在spring中注入上，那么就可以用了。也符合设计原则。当你的代码中大量的出现if else的话，就说明你的代码需要进行重构了，不然的话你只会被局限在这个一个小的空间里面，当你把它解耦出来后，你面对的视野和高度就不一样了，你所能做的事情就会超出原来的很多倍。

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