[LUCENE-9967] ReplicaNode.start NPE on exception with no message

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 8.8.2
• Fix Version/s: 8.9
• Component/s: modules/replicator
• Labels: easyfix patch

Environment

Java 16.0.1, Fedora Linux 33

• Lucene Fields: New, Patch Available
• Assignee: Unassigned
• Reporter: Steven Schlansker
• Created: 21/May/21 18:40
• Updated: 28/Aug/22 16:21
• Resolved: 24/May/21 15:53

Description

We are starting a new project and trying to implement Lucene near real time replication.

While stubbing out some code such that it throws an exception, we found that Lucene's error handling itself fails when the exception has no message:

 

    } catch (Throwable t) {
      if (t.getMessage().startsWith("replica cannot start") == false) {

 

This obscures the actual root cause exception source (you cannot see it without a debugger) and replaces it with a useless NPE.