NullPointerException in native Java code when executing parallelStream.forEach (..)

Question

I have the following exception (stacktrace):

java.lang.NullPointerException
at sun.reflect.GeneratedConstructorAccessor171.newInstance(Unknown Source) ~[?:?]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_40]
at java.lang.reflect.Constructor.newInstance(Constructor.java:422) ~[?:1.8.0_40]
at java.util.concurrent.ForkJoinTask.getThrowableException(ForkJoinTask.java:598) ~[?:1.8.0_40]
at java.util.concurrent.ForkJoinTask.reportException(ForkJoinTask.java:677) ~[?:1.8.0_40]
at java.util.concurrent.ForkJoinTask.invoke(ForkJoinTask.java:735) ~[?:1.8.0_40]
at java.util.stream.ForEachOps$ForEachOp.evaluateParallel(ForEachOps.java:160) ~[?:1.8.0_40]
at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateParallel(ForEachOps.java:174) ~[?:1.8.0_40]
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:233) ~[?:1.8.0_40]
at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418) ~[?:1.8.0_40]
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:583) ~[?:1.8.0_40]
at com.tradair.tnet.services.trades.TradeService.updateUnrealizedPNL(TradeService.java:173) ~[tnet.jar:5.1.1.0-SNAPSHOT]

which starts with my class TradeService:

    public void updateUnrealizedPNL(Set<Org> orgsToCaluclate, Set<Org> orgsToSendUpdate) {
    orgsToCaluclate.parallelStream().forEach(o -> {
        pnlService.updateMidPrices(o);
        Collection<SystemTradeOrder> allLiveTradesByOrgId = tradesRepository.getAllLiveTradesByOrgId(o.getId());
        updateUnrealizedPNL(o, allLiveTradesByOrgId);
    });

    // more code ....

So it looks like the exception is being thrown inside the java native code when the method starts forEach(..). I mean, it is NullPointerExceptionnot thrown out of my own code, and not from my consumer function, which appears as an argument in a method forEach(..).

I double-checked that the modification orgsToCaluclatedoes not change when this part of the code works.

This is the initialization orgsToCaluclate:

        Set<Org> orgsToCaluclate = getMarginOrgs();
        orgsToCaluclate = orgsToCaluclate.stream()
                .filter(org -> !isOrgInCloseout(org.getId())).collect(Collectors.toSet());

Any thoughts? ..

Answer 1

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2   s.length();

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1   String s=null;
2   if(s == null) {
3       RuntimeException rt=new NullPointerException();
4       throw rt;
5   }

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import java.util.stream.IntStream;

public class Main
{
    public static void main(String[] args) {
        Thread main=Thread.currentThread();
        IntStream.range(0, 1000).parallel().forEach(i -> {
            if(Thread.currentThread()!=main)
                throw new NullPointerException();
        });
    }
}

Exception in thread "main" java.lang.NullPointerException
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at java.util.concurrent.ForkJoinTask.getThrowableException(ForkJoinTask.java:598)
    at java.util.concurrent.ForkJoinTask.reportException(ForkJoinTask.java:677)
    at java.util.concurrent.ForkJoinTask.invoke(ForkJoinTask.java:735)
    at java.util.stream.ForEachOps$ForEachOp.evaluateParallel(ForEachOps.java:160)
    at java.util.stream.ForEachOps$ForEachOp$OfInt.evaluateParallel(ForEachOps.java:189)
    at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:233)
    at java.util.stream.IntPipeline.forEach(IntPipeline.java:404)
    at java.util.stream.IntPipeline$Head.forEach(IntPipeline.java:560)
    at Main.main(Main.java:7)
Caused by: java.lang.NullPointerException
    at Main.lambda$main$0(Main.java:9)
    at java.util.stream.ForEachOps$ForEachOp$OfInt.accept(ForEachOps.java:205)
    at java.util.stream.Streams$RangeIntSpliterator.forEachRemaining(Streams.java:110)
    at java.util.Spliterator$OfInt.forEachRemaining(Spliterator.java:693)
    at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
    at java.util.stream.ForEachOps$ForEachTask.compute(ForEachOps.java:291)
    at java.util.concurrent.CountedCompleter.exec(CountedCompleter.java:731)
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)

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import java.util.stream.IntStream;

public class Main
{
    public static class CustomException extends RuntimeException {
        public CustomException() {
            System.err.println("will deliberately fail");
            throw new NullPointerException();
        }
        private CustomException(String message) {
            super(message);
        }
    }
    public static void main(String[] args) {
        Thread main=Thread.currentThread();
        IntStream.range(0, 1000).parallel().forEach(i -> {
            if(Thread.currentThread()!=main)
                throw new CustomException("forced failure");
        });
    }
}

will deliberately fail
Exception in thread "main" Main$CustomException: forced failure
    at Main.lambda$main$0(Main.java:18)
    at java.util.stream.ForEachOps$ForEachOp$OfInt.accept(ForEachOps.java:205)
    at java.util.stream.Streams$RangeIntSpliterator.forEachRemaining(Streams.java:110)
    at java.util.Spliterator$OfInt.forEachRemaining(Spliterator.java:693)
    at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
    at java.util.stream.ForEachOps$ForEachTask.compute(ForEachOps.java:291)
    at java.util.concurrent.CountedCompleter.exec(CountedCompleter.java:731)
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)

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Answer 2

stacktrace, , , , - NullPointerException, , - , foreach .

    at java.lang.reflect.Constructor.newInstance(Constructor.java:422) ~[?:1.8.0_40]
at java.util.concurrent.ForkJoinTask.getThrowableException(ForkJoinTask.java:598) ~[?:1.8.0_40]
at java.util.concurrent.ForkJoinTask.reportException(ForkJoinTask.java:677) ~[?:1.8.0_40]
at java.util.concurrent.ForkJoinTask.invoke(ForkJoinTask.java:735) ~[?:1.8.0_40]