模版符合开闭原则，到处用于钩子方法。有的钩子方法不会改变行为，有的钩子会改变运行轨迹。框架中到处使用。
Channel中定义了需要的操作，AbstractChannel实现了核心功能，然后不同的Channel实现只需要告知具体channel的描述信息即可。
Channel 接口⬇︎⬇︎⬇︎
点击查看代码
package com.xxx.sales.subscription.service.pubsub;
import com.xxx.sales.subscription.service.pubsub.dto.SubscribersResult;
import com.xxx.sales.subscription.service.pubsub.enums.ChannelEnum;
/**
* 通道/频道
* <pre>
* 消息发送到指定的channel中， 各个订阅者监听channel
* </pre>
*
* @author huhaiyang
*/
public interface Channel<K, V extends SubscribersResult> {
/**
* 获得信道描述
*
* @return {@link ChannelEnum}
*/
ChannelEnum getChannelDescription();
/**
* 添加订阅者
*
* @param subscriber 订阅者
*/
void addSubscriber(SafetySubscriber<K, V> subscriber);
/**
* 删除订阅者
*
* @param subscriber 订阅者
*/
void removeSubscriber(SafetySubscriber<K, V> subscriber);
}
AbstractChannel 实现重要功能⬇︎⬇︎⬇︎
点击查看代码
package com.xxx.sales.subscription.service.pubsub.chanels;
import com.xxx.sales.subscription.service.pubsub.Channel;
import com.xxx.sales.subscription.service.pubsub.SafetySubscriber;
import com.xxx.sales.subscription.service.pubsub.dto.SubscriberResult;
import com.xxx.sales.subscription.service.pubsub.dto.SubscribersResult;
import lombok.extern.slf4j.Slf4j;
import java.util.LinkedList;
/**
*
* @author huhaiyang
*/
@Slf4j
public abstract class AbstractChannel<K, V extends SubscribersResult> implements Channel<K, V> {
private LinkedList<SafetySubscriber<K, V>> subscribers = new LinkedList<>();
/**
* 添加订阅者
*
* @param subscriber 订阅者
*/
@Override
public void addSubscriber(SafetySubscriber subscriber) {
if (subscribers.contains(subscriber)) {
return;
}else {
subscribers.add(subscriber);
}
}
/**
* 删除订阅者
*
* @param subscriber 订阅者
*/
@Override
public void removeSubscriber(SafetySubscriber subscriber) {
subscribers.remove(subscriber);
}
/**
* 接收消息
*
* @param message 消息
* @param collectResult 收集结果
*/
public void receiveMessage(K message,V collectResult){
log.info("receiveMessage start...");
for (SafetySubscriber<K, V> subscriber : subscribers) {
subscriber.update(message, collectResult);
SubscriberResult resultBySubscriber = collectResult.getResultBySubscriber(subscriber);
if (!resultBySubscriber.isSuccess()) {
log.info("{}执行失败，开始失败策略...",subscriber.getClass().getSimpleName());
subscriber.failBack(message,collectResult);
log.info("{}失败策略执行结束.",subscriber.getClass().getSimpleName());
}
}
log.info("receiveMessage end...");
}
}
OrderActivateChannel 订单激活channel ⬇︎⬇︎⬇︎
点击查看代码
package com.xxx.sales.subscription.service.pubsub.chanels;
import com.xxx.sales.subscription.service.pubsub.dto.OrderActivateMessage;
import com.xxx.sales.subscription.service.pubsub.dto.SubscribersResult;
import com.xxx.sales.subscription.service.pubsub.enums.ChannelEnum;
import org.springframework.stereotype.Component;
/**
* 订单激活的channel
*
* @author huhaiyang
* @date 2022 2022/12/8
*/
@Component
public class OrderActivateChannel extends AbstractChannel<OrderActivateMessage, SubscribersResult> {
/**
* 获得信道描述
*
* @return {@link ChannelEnum}
*/
@Override
public ChannelEnum getChannelDescription() {
return ChannelEnum.ORDER_ACTIVATE;
}
}
标签：service,模版,xxx,模式,subscriber,使用,import,com,pubsub From： https://www.cnblogs.com/euler-blog/p/18613233