[HDFS-dev] [jira] [Created] (HDFS-1934) Fix NullPointerException when certain File APIs return null

Fix NullPointerException when certain File APIs return null
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Key: HDFS-1934
URL: https://issues.apache.org/jira/browse/HDFS-1934
Project: Hadoop HDFS
Issue Type: Bug
Affects Versions: 0.20.205.0, 0.23.0
Reporter: Bharath Mundlapudi
Assignee: Bharath Mundlapudi
Fix For: 0.20.205.0, 0.23.0


While testing Disk Fail Inplace, We encountered the NPE from this part of the code.

File[] files = dir.listFiles();
for (File f : files) {
...
}

This is kinda of an API issue. When a disk is bad (or name is not a directory), this API (listFiles, list) return null rather than throwing an exception. This 'for loop' throws a NPE exception. And same applies to dir.list() API.

Fix all the places where null condition was not checked.