[GitHub] [carbondata] akashrn5 commented on a change in pull request #3907: [CARBONDATA-3966]Fix NullPointerException issue in case of reliability testing of load and compaction

[GitBox <gi...@apache.org>]

akashrn5 commented on a change in pull request #3907:
URL: https://github.com/apache/carbondata/pull/3907#discussion_r481198186



##########
File path: core/src/main/java/org/apache/carbondata/core/index/IndexStoreManager.java
##########
@@ -515,15 +516,16 @@ public TableSegmentRefresher getTableSegmentRefresher(CarbonTable table) {
         UpdateVO updateVO =
             SegmentUpdateStatusManager.getInvalidTimestampRange(segment.getLoadMetadataDetails());
         SegmentRefreshInfo segmentRefreshInfo;
-        if ((updateVO != null && updateVO.getLatestUpdateTimestamp() != null)
-            || segment.getSegmentFileName() != null) {
-          long segmentFileTimeStamp;
+        if (updateVO.getLatestUpdateTimestamp() != null || segment.getSegmentFileName() != null) {
+          long segmentFileTimeStamp = 0L;
           if (null != segment.getLoadMetadataDetails()) {
             segmentFileTimeStamp = segment.getLoadMetadataDetails().getLastModifiedTime();
           } else {
-            segmentFileTimeStamp = FileFactory.getCarbonFile(CarbonTablePath
-                .getSegmentFilePath(table.getTablePath(), segment.getSegmentFileName()))
-                .getLastModifiedTime();
+            CarbonFile segmentFile = FileFactory.getCarbonFile(CarbonTablePath
+                .getSegmentFilePath(table.getTablePath(), segment.getSegmentFileName()));
+            if (segmentFile.exists()) {

Review comment:
       1. even though when the segment object exists, if concurrently operations are happening like like or compaction, you can consider SI also, then we will modify the segment file, which is basically overwrite, then that corner case it will fail, so in that case, above scenario will happen, so no need to throw exception.
   
   2. can refer PR #3814 
   
   3. we cannot differentiate between positive case and negative case, in order to query or the operation to succeed, we should take these steps, which we follow all places in carbon.




----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org