使用guava ConcurrentHashSet解决core.push.BroadcastPushTask的多线程ConcurrentModificationException异常

[simplexity-ckcclc]

Broadcast下做流控，异步发送成功future结束后会更新successUserIds的值。同时发送后流控统计数据时会调用successUserIds#toArray()方法。successUserIds的数据结构为HashSet非线程安全，在toArray过程中更新会抛出以下异常。

2018-05-10 09:29:29.749 - [mp-gateway-work-5-2] WARN  - i.n.u.c.AbstractEventExecutor - A task raised an exception. Task: com.mpush.core.push.BroadcastPushTask@79877a99
java.util.ConcurrentModificationException: null
        at java.util.HashMap$HashIterator.nextNode(HashMap.java:1442)
        at java.util.HashMap$KeyIterator.next(HashMap.java:1466)
        at java.util.AbstractCollection.toArray(AbstractCollection.java:196)
        at com.mpush.core.push.BroadcastPushTask.run(BroadcastPushTask.java:87)
        at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasksFrom(SingleThreadEventExecutor.java:379)
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:354)
        at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:292)
        at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
        at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:144)
        at java.lang.Thread.run(Thread.java:748)

[justein]

maybe