question Re: HDF 2.1: Warnings, frequently, can't track down in Archives of Support Questions (Read Only)

HDF 2.1: Warnings, frequently, can't track down

TimothySpann — Tue, 21 Apr 2026 12:25:29 GMT

2017-01-30 16:38:39,425 WARN [Timer-Driven Process Thread-9] o.a.n.c.t.ContinuallyRunProcessorTask java.lang.IndexOutOfBoundsException: No group 1 at java.util.regex.Matcher.start(Matcher.java:375) ~[na:1.8.0_77] at java.util.regex.Matcher.appendReplacement(Matcher.java:880) ~[na:1.8.0_77] at java.util.regex.Matcher.replaceAll(Matcher.java:955) ~[na:1.8.0_77] at java.lang.String.replaceAll(String.java:2223) ~[na:1.8.0_77] at org.apache.nifi.processors.standard.ReplaceText$RegexReplace.replace(ReplaceText.java:518) ~[na:na] at org.apache.nifi.processors.standard.ReplaceText.onTrigger(ReplaceText.java:263) ~[na:na] at org.apache.nifi.processor.AbstractProcessor.onTrigger(AbstractProcessor.java:27) ~[nifi-api-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2] at org.apache.nifi.controller.StandardProcessorNode.onTrigger(StandardProcessorNode.java:1099) ~[nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2] at org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:136) [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2] at org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:47) [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2] at org.apache.nifi.controller.scheduling.TimerDrivenSchedulingAgent$1.run(TimerDrivenSchedulingAgent.java:132) [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2] at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_77] at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) [na:1.8.0_77] at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180) [na:1.8.0_77] at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294) [na:1.8.0_77] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_77] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_77] at java.lang.Thread.run(Thread.java:745) [na:1.8.0_77]

Re: HDF 2.1: Warnings, frequently, can't track down

andrewg — Tue, 31 Jan 2017 01:12:43 GMT

Tim,

It looks like the regex you're using might need more work to account for optional matches. The ReplaceText processor is complaining about missing match groups and has no context to do the replacement.

Re: HDF 2.1: Warnings, frequently, can't track down

jwhitmore — Sun, 18 Aug 2019 12:45:25 GMT

@Timothy Spann,

I don't have a solution, yet, but I think that ReplaceText is doing recursive replacement of some sort. It is replacing the value with the requested attribute, but it is then evaluating that replacement again, including a new $2, but there is no group 2 captured in the search.

I find that this happens if the attribute I'm replacing has a dollar sign followed by a number in it. For instance, the following replace text is going to put the user.name attribute into the flowfile:

However, when the attribute has a $2 in it, I get an IndexOutOfBounds error and the offending flowfile stays in the upstream queue.

Here are the flowfile attributes that show a $2 in the middle of the user.name attribute.

I get the same issue with "no group 6" if the name has $6 in it.

I'm going to try some of the quoting functions to see if that changes the behavior.

John