GitHub user wangyum opened a pull request: https://github.com/apache/spark/pull/23164
[SPARK-26198][SQL] Fix Metadata serialize null values throw NPE ## What changes were proposed in this pull request? How to reproduce this issue: ```scala scala> val meta = new org.apache.spark.sql.types.MetadataBuilder().putNull("key").build() java.lang.NullPointerException at org.apache.spark.sql.types.Metadata$.org$apache$spark$sql$types$Metadata$$toJsonValue(Metadata.scala:196) at org.apache.spark.sql.types.Metadata$$anonfun$1.apply(Metadata.scala:180) ``` This pr fix `NullPointerException` when `Metadata` serialize `null` values. ## How was this patch tested? unit tests You can merge this pull request into a Git repository by running: $ git pull https://github.com/wangyum/spark SPARK-26198 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/spark/pull/23164.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #23164 ---- commit 03101868a72b5ae68bf6324e627f1874af32f040 Author: Yuming Wang <yumwang@...> Date: 2018-11-28T12:22:09Z Fix Metadata serialize null values throw NPE ---- --- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org