[ https://issues.apache.org/jira/browse/FLINK-4862?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Maximilian Michels updated FLINK-4862: -------------------------------------- Fix Version/s: (was: 1.14) 1.1.4 > NPE on EventTimeSessionWindows with ContinuousEventTimeTrigger > -------------------------------------------------------------- > > Key: FLINK-4862 > URL: https://issues.apache.org/jira/browse/FLINK-4862 > Project: Flink > Issue Type: Bug > Components: Streaming, Windowing Operators > Affects Versions: 1.2.0, 1.1.3 > Reporter: Manu Zhang > Fix For: 1.2.0, 1.1.4 > > > h3. what's the error ? > The following NPE error is thrown when EventTimeSessionWindows with > ContinuousEventTimeTrigger is used. > {code} > Caused by: java.lang.NullPointerException > at > org.apache.flink.streaming.api.windowing.triggers.ContinuousEventTimeTrigger.clear(ContinuousEventTimeTrigger.java:91) > at > org.apache.flink.streaming.runtime.operators.windowing.WindowOperator$Context.clear(WindowOperator.java:768) > at > org.apache.flink.streaming.runtime.operators.windowing.WindowOperator$2.merge(WindowOperator.java:310) > at > org.apache.flink.streaming.runtime.operators.windowing.WindowOperator$2.merge(WindowOperator.java:297) > at > org.apache.flink.streaming.runtime.operators.windowing.MergingWindowSet.addWindow(MergingWindowSet.java:196) > at > org.apache.flink.streaming.runtime.operators.windowing.WindowOperator.processElement(WindowOperator.java:297) > at > org.apache.flink.streaming.runtime.io.StreamInputProcessor.processInput(StreamInputProcessor.java:183) > at > org.apache.flink.streaming.runtime.tasks.OneInputStreamTask.run(OneInputStreamTask.java:66) > at > org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:271) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:609) > at java.lang.Thread.run(Thread.java:745) > {code} > h3. how to reproduce ? > use {{ContinuousEventTimeTrigger}} instead of the default > {{EventTimeTrigger}} in [SessionWindowing | > https://github.com/apache/flink/blob/master/flink-examples/flink-examples-streaming/src/main/java/org/apache/flink/streaming/examples/windowing/SessionWindowing.java#L84] > example. > h3. what's the cause ? > When two session windows are being merged, the states of the two > {{ContinuousEventTimeTrigger}} are merged as well and the new namespace is > the merged window. Later when the context tries to delete {{Timer}} from the > old trigger and looks up the timestamp by the old namespace, null value is > returned. -- This message was sent by Atlassian JIRA (v6.3.4#6332)