Nepxion EventBus是一款基于Google Guava通用事件派发机制的事件总线组件,它采用Spring Framework AOP机制,提供注解调用方式,支持异步和同步两种方式
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- 实现基于@EventBus注解开启EventBus机制
- 实现异步模式下(默认),子线程中收到派发的事件,基于@EventBus(async = false),来切换是同步还是异步
- 实现批量派发事件
- 实现同步模式下,主线程中收到派发的事件
- 实现线程隔离技术,并定制化配置线程池
- 实现事件对象的多元化,可以发布和订阅Java基本类型,也可以利用框架内置的Event类型,当然也可以使用任意自定义类型
最新版本兼容
- Spring 4.x.x和Spring Boot 1.x.x
- Spring 5.x.x和Spring Boot 2.x.x
<dependency>
<groupId>com.nepxion</groupId>
<artifactId>eventbus-aop-starter</artifactId>
<version>${eventbus.version}</version>
</dependency>
@SpringBootApplication
@EnableEventBus
public class MyApplication {
}
- EventBus事件控制器(Controller)策略
- 可以由单个Controller控制缺省identifier的EventBus事件(在Google Guava内部定义缺省identifier的值为'default')。用法如下:
事件发布端:
eventControllerFactory.getAsyncController().post("abc"); // 异步发送
eventControllerFactory.getSyncController().post("abc"); // 同步发送
事件订阅端:
@EventBus // 订阅异步消息,async不指定,默认为true
public class MySubscriber {
}
@EventBus(async = false) // 订阅同步消息
public class MySubscriber {
}
- 可以由多个Controller控制不同identifier的EventBus事件。用法如下:
事件发布端:
eventControllerFactory.getAsyncController(identifier).post("abc"); // 异步发送
eventControllerFactory.getSyncController(identifier).post("abc"); // 同步发送
事件订阅端:
@EventBus(identifier = "xyz") // 订阅异步消息,async不指定,默认为true
public class MySubscriber {
}
@EventBus(identifier = "xyz", async = false) // 订阅同步消息
public class MySubscriber {
}
注意:事件发布端和订阅端的identifier一定要一致
# EventBus config
# 开关配置,结合注解@EnableEventBus使用
# eventbus.enabled=true
- EventBus线程池(ThreadPool)策略
- 配置如下: 线程池配置,参考application.properties,可以不需要配置,那么采取如下默认值
# Thread Pool Config
# Multi thread pool,是否线程隔离。如果是,那么每个不同identifier的事件都会占用一个单独线程池,否则共享一个线程池
threadPoolMultiMode=false
# 共享线程池的名称
threadPoolSharedName=EventBus
# 是否显示自定义的线程池名
threadPoolNameCustomized=true
# CPU unit(CPU核数单位,例如在8核心CPU上,threadPoolCorePoolSize配置为2,那么最终核心线程数为16,下同)
threadPoolCorePoolSize=1
# CPU unit
threadPoolMaximumPoolSize=2
threadPoolKeepAliveTime=900000
threadPoolAllowCoreThreadTimeout=false
# LinkedBlockingQueue, ArrayBlockingQueue, SynchronousQueue
threadPoolQueue=LinkedBlockingQueue
# CPU unit (Used for LinkedBlockingQueue or ArrayBlockingQueue)
threadPoolQueueCapacity=128
# BlockingPolicyWithReport, CallerRunsPolicyWithReport, AbortPolicyWithReport, RejectedPolicyWithReport, DiscardedPolicyWithReport
threadPoolRejectedPolicy=BlockingPolicyWithReport
调用入口1,异步模式(默认)下接收事件
package com.nepxion.eventbus.example.service;
/**
* <p>Title: Nepxion EventBus</p>
* <p>Description: Nepxion EventBus AOP</p>
* <p>Copyright: Copyright (c) 2017-2050</p>
* <p>Company: Nepxion</p>
* @author Haojun Ren
* @version 1.0
*/
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import com.google.common.eventbus.Subscribe;
import com.nepxion.eventbus.annotation.EventBus;
import com.nepxion.eventbus.core.Event;
@EventBus
@Service
public class MySubscriber1 {
private static final Logger LOG = LoggerFactory.getLogger(MySubscriber1.class);
@Subscribe
public void subscribe(String event) {
LOG.info("子线程接收异步事件 - {},String类型", event);
}
@Subscribe
public void subscribe(Long event) {
LOG.info("子线程接收异步事件 - {},Long类型", event);
}
@Subscribe
public void subscribe(Boolean event) {
LOG.info("子线程接收异步事件 - {},Boolean类型", event);
}
@Subscribe
public void subscribe(Event event) {
LOG.info("子线程接收异步事件 - {},内置类型Event", event);
}
}
调用入口2,同步模式下接收事件
package com.nepxion.eventbus.example.service;
/**
* <p>Title: Nepxion EventBus</p>
* <p>Description: Nepxion EventBus AOP</p>
* <p>Copyright: Copyright (c) 2017-2050</p>
* <p>Company: Nepxion</p>
* @author Haojun Ren
* @version 1.0
*/
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import com.google.common.eventbus.Subscribe;
import com.nepxion.eventbus.annotation.EventBus;
import com.nepxion.eventbus.core.Event;
@EventBus(async = false)
@Service
public class MySubscriber2 {
private static final Logger LOG = LoggerFactory.getLogger(MySubscriber2.class);
@Subscribe
public void subscribe(String event) {
LOG.info("主线程接收同步事件 - {},String类型", event);
}
@Subscribe
public void subscribe(Long event) {
LOG.info("主线程接收同步事件 - {},Long类型", event);
}
@Subscribe
public void subscribe(Boolean event) {
LOG.info("主线程接收同步事件 - {},Boolean类型", event);
}
@Subscribe
public void subscribe(Event event) {
LOG.info("主线程接收同步事件 - {},内置类型Event", event);
}
}
调用入口3,派发事件
package com.nepxion.eventbus.example.service;
/**
* <p>Title: Nepxion EventBus</p>
* <p>Description: Nepxion EventBus AOP</p>
* <p>Copyright: Copyright (c) 2017-2050</p>
* <p>Company: Nepxion</p>
* @author Haojun Ren
* @version 1.0
*/
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.nepxion.eventbus.core.Event;
import com.nepxion.eventbus.core.EventControllerFactory;
@Service
public class MyPublisher {
private static final Logger LOG = LoggerFactory.getLogger(MyPublisher.class);
@Autowired
private EventControllerFactory eventControllerFactory;
public void publish() {
LOG.info("发送事件...");
// 异步模式下(默认),子线程中收到派发的事件
eventControllerFactory.getAsyncController().post("Sync Event String Format");
// 同步模式下,主线程中收到派发的事件
// 事件派发接口中eventControllerFactory.getSyncController(identifier)必须和@EnableEventBus参数保持一致,否则会收不到事件
eventControllerFactory.getSyncController().post("Sync Event String Format");
// 异步模式下(默认),子线程中收到派发的事件
eventControllerFactory.getAsyncController().post(12345L);
// 同步模式下,主线程中收到派发的事件
// 事件派发接口中eventControllerFactory.getSyncController(identifier)必须和@EnableEventBus参数保持一致,否则会收不到事件
eventControllerFactory.getSyncController().post(Boolean.TRUE);
// 异步模式下(默认),子线程中收到派发的事件
eventControllerFactory.getAsyncController().postEvent(new Event("Async Event"));
// 同步模式下,主线程中收到派发的事件
// 事件派发接口中eventControllerFactory.getSyncController(identifier)必须和@EnableEventBus参数保持一致,否则会收不到事件
eventControllerFactory.getSyncController().postEvent(new Event("Sync Event"));
}
}
主入口
package com.nepxion.eventbus.example;
/**
* <p>Title: Nepxion EventBus</p>
* <p>Description: Nepxion EventBus AOP</p>
* <p>Copyright: Copyright (c) 2017-2050</p>
* <p>Company: Nepxion</p>
* @author Haojun Ren
* @version 1.0
*/
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import com.nepxion.eventbus.annotation.EnableEventBus;
import com.nepxion.eventbus.example.service.MyPublisher;
@SpringBootApplication
@EnableEventBus
public class MyApplication {
public static void main(String[] args) throws Exception {
ConfigurableApplicationContext applicationContext = SpringApplication.run(MyApplication.class, args);
MyPublisher myPublisher = applicationContext.getBean(MyPublisher.class);
myPublisher.publish();
}
}
运行结果
2018-06-25 13:01:02.008 INFO [main][com.nepxion.eventbus.example.service.MyPublisher:28] - 发送事件...
2018-06-25 13:01:02.015 INFO [EventBus-192.168.0.107-thread-0][com.nepxion.eventbus.example.service.MySubscriber1:27] - 子线程接收异步事件 - Sync Event String Format,String类型
2018-06-25 13:01:02.016 INFO [main][com.nepxion.eventbus.example.service.MySubscriber2:27] - 主线程接收同步事件 - Sync Event String Format,String类型
2018-06-25 13:01:02.016 INFO [main][com.nepxion.eventbus.example.service.MySubscriber2:37] - 主线程接收同步事件 - true,Boolean类型
2018-06-25 13:01:02.016 INFO [EventBus-192.168.0.107-thread-1][com.nepxion.eventbus.example.service.MySubscriber1:32] - 子线程接收异步事件 - 12345,Long类型
2018-06-25 13:01:02.017 INFO [EventBus-192.168.0.107-thread-2][com.nepxion.eventbus.example.service.MySubscriber1:42] - 子线程接收异步事件 - com.nepxion.eventbus.core.Event@67ca8c1f[
source=Async Event
],内置类型Event
2018-06-25 13:01:02.017 INFO [main][com.nepxion.eventbus.example.service.MySubscriber2:42] - 主线程接收同步事件 - com.nepxion.eventbus.core.Event@1bcf67e8[
source=Sync Event
],内置类型Event