com.kaka.notice.RemoteMessagePostman Maven / Gradle / Ivy
package com.kaka.notice;
import com.kaka.util.StringUtils;
import java.util.Map;
/**
* 远端事件处理器
* 目前一个事件仅支持获取一次处理结果，即广播状态，事件处理结果以最先获得为准，后面获得的处理结果直接丢弃
* 分布式环境需谨慎使用事件远端广播，因广播事件时所有拥有事件逻辑处理器{@link Command}的远程服务都将处理事件逻辑
*
* @author zkpursuit
*/
abstract public class RemoteMessagePostman {
protected Facade facade;
protected final RemoteMessageCache remoteMessageCache;
protected final String event_topic; //收到远端事件数据后处理事件
protected final String event_result_topic; //收到远端事件处理后的结果给本地缓存的事件赋值处理结果
/**
* 处理远端事件
*/
private static class RemoteMessageMediator extends Mediator {
private final RemoteMessagePostman postman;
RemoteMessageMediator(RemoteMessagePostman postman) {
super("remote_message_mediator_" + StringUtils.randomString(16, true));
this.postman = postman;
}
@Override
public void handleMessage(Message msg) {
RemoteMessage remoteMessage = (RemoteMessage) msg;
String cmd = msg.getWhat().toString();
if (this.postman.event_topic.equals(cmd)) {
//接收远端事件并执行事件处理逻辑
String id = remoteMessage.id;
Message localEventMessage = this.postman.remoteMessageCache.remove(id);
if (localEventMessage != null) {
//远端事件接收方如果与事件发送方同源则直接处理
this.sendMessage(localEventMessage);
return;
}
Message remoteEventMessage = (Message) remoteMessage.getBody();
this.sendMessage(remoteEventMessage);
if (remoteEventMessage.resultMap != null && !remoteEventMessage.resultMap.isEmpty()) {
remoteMessage.what = this.postman.event_result_topic;
this.postman.sendRemoteMessage(remoteMessage);
}
return;
}
if (this.postman.event_result_topic.equals(cmd)) {
//事件消息发送方接收到来自远端的处理结果
String id = remoteMessage.id;
Message remoteEventMessage = (Message) remoteMessage.getBody();
Message localEventMessage = this.postman.remoteMessageCache.remove(id);
if (localEventMessage == null) {
this.getFacade().sendMessage(new Message("remote_processed_message", remoteEventMessage));
return;
}
Map eventResultMap = remoteEventMessage.resultMap;
if (eventResultMap == null) return;
eventResultMap.forEach((Object key, IResult result) -> {
String keyStr = String.valueOf(key);
IResult localResult = localEventMessage.getResult(keyStr);
if (localResult instanceof AsynResult) {
localResult.set(result.get());
} else if (result instanceof CallbackResult) {
localEventMessage.setResult(keyStr, result);
localEventMessage.callback(keyStr);
}
});
}
}
@Override
public Object[] listMessageInterests() {
return new Object[]{this.postman.event_topic, this.postman.event_result_topic};
}
}
/**
* 构造方法
*
* @param event_topic 收到远端事件数据后处理事件
* @param event_result_topic 收到远端事件处理后的结果给本地缓存的事件赋值处理结果
*/
public RemoteMessagePostman(String event_topic, String event_result_topic) {
this.remoteMessageCache = this.initRemoteMessageCache();
this.event_topic = event_topic;
this.event_result_topic = event_result_topic;
}
/**
* 包内赋值事件总线
*
* @param facade 事件总线，事件分发器
*/
void setFacade(Facade facade) {
this.facade = facade;
this.facade.registerMediator(new RemoteMessageMediator(this));
}
/**
* 初始化事件消息处理器缓存
*
* @return 事件消息处理器缓存
*/
abstract protected RemoteMessageCache initRemoteMessageCache();
/**
* 发送远端消息
*
* @param remoteMessage 事件消息
*/
protected abstract void sendRemoteMessage(RemoteMessage remoteMessage);
}