FULL PRODUCT VERSION :
java version "1.8.0_31"
Java(TM) SE Runtime Environment (build 1.8.0_31-b13)
Java HotSpot(TM) Server VM (build 25.31-b07, mixed mode)

as well as

java version "1.8.0_40"
Java(TM) SE Runtime Environment (build 1.8.0_40-b25)
Java HotSpot(TM) 64-Bit Server VM (build 25.40-b25, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux svn 2.6.32-58-generic-pae #121-Ubuntu SMP Fri May 2 21:49:01 UTC 2014 i686 GNU/Linux
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 10.04.4 LTS
Release: 10.04
Codename: lucid

as well as

Linux fireball 3.16.0-31-generic #43-Ubuntu SMP Tue Mar 10 17:37:36 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

Distributor ID: Ubuntu
Description: Ubuntu 14.10
Release: 14.10
Codename: utopic


A DESCRIPTION OF THE PROBLEM :
Very occasionally I get a NullPointException at the following path:

java.lang.RuntimeException: null
at java.util.concurrent.CompletableFuture.timedAwaitDone(CompletableFuture.java:365)
at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2260)

I understand that at the given path no NPE should be thrown.

I get this exception on our jenkins-Buildserver about once per 20 Tests.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Reproduction is not easily possible, whenever I try to provoke the error, it will run for quite a long time.


ERROR MESSAGES/STACK TRACES THAT OCCUR :
java.lang.RuntimeException: null
at java.util.concurrent.CompletableFuture.timedAwaitDone(CompletableFuture.java:365)
at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2260)


REPRODUCIBILITY :
This bug can be reproduced occasionally.

CUSTOMER SUBMITTED WORKAROUND :
No workaround nown