关于这三种设计模式是什么这里就不再赘述，本篇文章主要讲的是应用，不理解概念的可以先看一下我的其他关于讲解设计模式的文章，接下来直接进入主题。
书接上文讲的策略+简单工厂模式，本次我们又引入了模板方法，将一些公用的方法定义在抽象类的方法中，不同子类各自实现各自的逻辑。
我们这次还是根据不同的渠道类型进行通知客户(渠道类型有短信sms、邮件email、钉钉dingTalk）
首先就是要有策略接口，接口里面要有一个方法就是通知的方法
java
public interface PushChannelStrategy｛
SendResult send(MessagePushParam param，BaseMsg baseMsg）;
｝然后是抽象类，抽象类中定义发送的通用流程，各自具体发送流程下沉到各自实现类
java
@Component
public abstract class AbstractPushChannelStrategy implements PushChannelStrategy{
@Override
public SendResult send(MessagePushParam parma,BaseMsg baseMsg){
// 获取目标地址，各自实现类来获取receiveAddress
ReceiverResult receiverResult =getReceiverAddress（param）；
// 拿到通知的地址，即手机号、邮箱、钉钉id
String receiverAddress=receiverResult.getReceiverAddress();
// 非空校验
if(StringUtils.isBlank(receiverAddress)){
return new SendResult(MessageStatusEnum.SEND_ADDRESS_NOT_EXIST,param.getReceiverId(),receiverAddress);
}
// 开始发送(短信、邮件、钉钉)，各自实现发送逻辑
return send(param,receiverAddress,baseMsg);
}
//获取目标地址
public abstract ReceiverResult getReceiverAddress(MessagePushParam param);
// 具体发送逻辑
public abstract SendResult send(MessagePushParam param,String targetId,BaseMsg BaseMsg);
然后三个子类短信、邮件、钉钉
java
@Slf4j
@Component
public class SmsPushChannelStrategy extends AbstractPushChannelStrategy｛
@Autowired
private NoticeClient noticeClient；
@Autowired
private CustomerGateway customerGateway；
@Override
public SendResult send（MessagePushParam param，String targetId，BaseMsg baseMsg）｛
//1、send sms
if(baseMsg instanceof Sms){
Sms smsMsg=(Sms)baseMsg;
NoticeResult noticeResult=noticeClient.sendSms（xxxx）；
SendResult sendResult=new SendResult();
sendResult.setMessageStatus（MessageStatusEnum.SUCCESS）；
return sendResult；
}
throw new MessagePushException("渠道不支持该类型消息");
｝
// 短信通知获取需要通知的手机号
@Override
public ReceiverResult getReceiverAddress(MessagePushParam param){
if(param==null){
return ReceiverResult.builder().status(MessageStatusEnum.SMS_QUERY_PARAM_NULL).build();
}
return customerGateway.getSmsResultByCustId(param.getCustomerId());
}
}邮件：
java
@Slf4j
@Component
public class EmailPushChannelStrategy extends AbstractPushChannelStrategy｛
@Autowired
private NoticeClient noticeClient；
@Autowired
private CustomerGateway customerGateway；
@Override
public SendResult send（MessagePushParam param，String targetId，BaseMsg baseMsg）｛
//1、send email
if(baseMsg instanceof Email){
Email emailMsg=(Email)baseMsg；
NoticeResult noticeResult=noticeClient.sendEmail（xxxx）；
sendResult.setMessageStatus（MessageStatusEnum.SUCCESS）；
return sendResult；
}
throw new MessagePushException(xxx);
｝
@Override
public ReceiverResult getReceiverAddress(MessagePushParam param){
if(param==null){
return ReceiverResult.builder().status(xxx).build();
}
return customerGateway.getEmailResultByCustId(param.getCustomerId());
｝
}钉钉：
java
@Slf4j
@Component
public class DingTalkPushChannelStrategy extends AbstractPushChannelStrategy｛
@Autowired
private DingTalkClient dingTalkClient；
@Autowired
private SalesGateway salesGateway;
@Override
public SendResult send（MessagePushParam param，BaseMsg baseMsg）｛
//1、send ding talk
SendResult sendResult=dingTalkClient.send(xxx)；
sendResult.setReceiverId（param.getSalesId());
// 其他结果参数组装
return sendResult；
｝
// 根据销售id获取钉钉id
@Override
public ReceiverResult getReceiverAddress(MessagePushParam param){
DingTalkResult dingTalkResult=salesGateway.getDingTalkResultBySalesId(param.getSalesId());
if(dingTalkResult==null){
return ReceiverResult.builder().status(xxx).receiverAddress(null).build();
}
return ReceiverResult.builder().status(MessageStatusEnum.SUCCESS).receiverAddress(dingTalkResult.getDingTalkId()).build();
｝
}然后通过策略工厂来获取具体的策略类：(由于只有三个策略类，所以通过注入的方式对channel进行判断)
java
@Component
public class PushChannelStrategyFactory｛
@Autowired
private DingTalkPushChannelStrategy dingTalkPushChannelStrategy；
@Autowired
private SmsPushChannelStrategy smsPushChannelStrategy；
@Autowired
private EmailPushChannelStrategy emailPushChannelStrategy；
public PushChannelStrategy getStrategy(PushChannel pushChannel)｛
switch(pushChannel)｛
case DING_TALK：
return dingTalkPushChannelStrategy；
case SMS：
return smsPushChannelStrategy；
case EMAIL：
return emailPushChannelStrategy；
default：
throw new RuntimeException(＂不支持的类型＂)；
｝
｝
｝当然策略工厂针对策略实现类比较少的情况还可以这样写：
java
@Component
public class PushChannelStrategyFactory2｛
@Autowired
private DingTalkPushChannelStrategy dingTalkPushChannelStrategy;
@Autowired
private SmsPushChannelStrategy smsPushChannelStrategy;
@Autowired
private EmailPushChannelStrategy emailPushChannelStrategy;
private static final Map<PushChannel,PushChannelStrategy> pushChannelBuilderMap=new HashMap<>();
@PostConstruct
public void init(){
pushChannelBuilderMap.put(PushChannel.SMS,smsPushChannelStrategy);
pushChannelBuilderMap.put(PushChannel.Email,emailPushChannelStrategy);
pushChannelBuilderMap.put(PushChannel.DING_TALK,dingTalkPushChannelStrategy);
}
Public PushChannelStrategy getStrategy(PushChannel PushChannel){
if(PushChannel==null){
return null;
}
return pushChannelBuilderMap.get(PushChannel);
}
}
枚举类：
java
@Getter
public enum PushChannel{
SMS(＂sms＂，＂短信＂），
EMAIL(＂email＂，＂邮件＂），
DING_TALK(＂dingTalk＂，＂钉钉＂）；
private final String value;
PushChannel(String value,String desc){
this.value=value;
}
public static PushChannel getPushChannel(String pushChannel){
if(pushChannel==null){
return null;
}
for(PushChannel channel:PushChannel.values()){
if(pushChannel.equals(channel.getValue())){
return channel;
}
}
return null;
}
}
在使用的时候通过策略工厂里面的方法获取具体的策略类：
java
@Slf4j
@Service
public class MessagePushService{
@Autowired
private PushChannelStrategyFactory pushChannelStrategyFactory;
@Autowired
private MessageRecordRepository messageRecordRepository;
public ResultDTO<Boolean> pushSync(MessagePushCommand command){
MessagePushParam messagePushParam =MessagePushAssembler.convert(command);
//1,业务逻辑处理
//2、根据渠道进行触达
PushChannel pushChannel=messagePushParam.getChannel();
if(pushChannel==null){
throw new MessagePushException(xxx);
}
//3、获取具体的策略类
PushChannelStrategy PushChannelStrategy=pushChannelStrategyFactory.getStrategy(pushChannel);
SendResult sendResult=PushChannelStrategy.send(messagePushParam,xxx);
//4,记录落库
return ResultDTO.getSuccessResult（true）；
｝
｝到此就结束了，是不是比较简单，该案例为实际项目中用到的实际案例，并且这三种设计模式也是比较简单和比较常用的设计模式，欢迎各位指出不足之处以及共同成长与学习。