Searched on Google with the first line of a JAVA stack trace?

We can recommend more relevant solutions and speed up debugging when you paste your entire stack trace with the exception message. Try a sample exception.

Recommended solutions based on your search

Solutions on the web

via Atlassian JIRA by Xavier Sanchez [Atlassian], 1 year ago
element cannot be mapped to a null key 2016-04-01 13:09:09.751755500 at java.util.Objects.requireNonNull(Objects.java:228) 2016-04-01 13:09:09.751756500 at java.util.stream.Collectors.lambda$groupingBy$176(Collectors.java:907) 2016-04-01 13:09:09.751756500 at java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169)
via Atlassian JIRA by Xavier Sanchez [Atlassian], 1 year ago
element cannot be mapped to a null key 2016-04-01 13:09:09.751755500 at java.util.Objects.requireNonNull(Objects.java:228) 2016-04-01 13:09:09.751756500 at java.util.stream.Collectors.lambda$groupingBy$176(Collectors.java:907) 2016-04-01 13:09:09.751756500 at java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169)
java.lang.NullPointerException: element cannot be mapped to a null key
2016-04-01 13:09:09.751755500 	at java.util.Objects.requireNonNull(Objects.java:228)
2016-04-01 13:09:09.751756500 	at java.util.stream.Collectors.lambda$groupingBy$176(Collectors.java:907)
2016-04-01 13:09:09.751756500 	at java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169)	at java.util.ArrayList.forEach(ArrayList.java:1249)	at java.util.stream.SortedOps$RefSortingSink.end(SortedOps.java:390)	at java.util.stream.Sink$ChainedReference.end(Sink.java:258)