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Ted Yu commented on HBASE-20611: -------------------------------- {code} + * Use poll() whenever possible. {code} Can you clarify the above - poll is not part of Iterator ? {code} + if (index < size()) + return (E) BoundedPriorityBlockingQueue.this.queue.objects[index++]; {code} Enclose return in pair of curlies. {code} + private final class Itr implements Iterator<CallRunner> { + private int index = 0; + private Object[] crArray = AdaptiveLifoCoDelCallQueue.this.queue.toArray(); {code} Why modification count is not involved in the above Iterator ? > UnsupportedOperationException may thrown when calling getCallQueueInfo() > ------------------------------------------------------------------------ > > Key: HBASE-20611 > URL: https://issues.apache.org/jira/browse/HBASE-20611 > Project: HBase > Issue Type: Bug > Affects Versions: 2.0.0 > Reporter: Allan Yang > Assignee: Xu Cang > Priority: Major > Attachments: HBASE-20611.master.002.patch, > HBASE-20611.master.003.patch, HBASE-20611.master.004.patch, > HBASE-20611.master.005.patch > > > HBASE-16290 added a new feature to dump queue info, the method > getCallQueueInfo() need to iterate the queue to get the elements in the > queue. But, except the Java's LinkedBlockingQueue, the other queue > implementations like BoundedPriorityBlockingQueue and > AdaptiveLifoCoDelCallQueue don't implement the method iterator(). If those > queues are used, a UnsupportedOperationException will be thrown. > This can be easily be reproduced by the UT testCallQueueInfo while adding a > conf: conf.set("hbase.ipc.server.callqueue.type", "deadline") > {code} > java.lang.UnsupportedOperationException > at > org.apache.hadoop.hbase.util.BoundedPriorityBlockingQueue.iterator(BoundedPriorityBlockingQueue.java:285) > at > org.apache.hadoop.hbase.ipc.RpcExecutor.getCallQueueCountsSummary(RpcExecutor.java:166) > at > org.apache.hadoop.hbase.ipc.SimpleRpcScheduler.getCallQueueInfo(SimpleRpcScheduler.java:241) > at > org.apache.hadoop.hbase.ipc.TestSimpleRpcScheduler.testCallQueueInfo(TestSimpleRpcScheduler.java:164) > {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005)