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。
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。