commit 90f44d9d62edf0fee5543adf48441a7a205f29f4
author Bernhard Geisberger <bernhard.geisberger@abusix.com> Tue Jan 26 15:29:30 2021 +0100
committer Mike Thomsen <mthomsen@apache.org> Wed Jun 16 14:07:16 2021 -0400
tree 22a6da4957b64a8d96ed81593edaadf03ed24cf9
parent 9be9b9dbe2ba574ab71321bdbb70defcfb59078b

NiFi-8152: Fix NPE in RedisDistributedMapCacheClientService caused by newer versions of Jedis

This closes #4783

Signed-off-by: Mike Thomsen <mthomsen@apache.org>

nifi-nar-bundles/nifi-redis-bundle/nifi-redis-extensions/src/main/java/org/apache/nifi/redis/service/RedisDistributedMapCacheClientService.java

diff --git a/nifi-nar-bundles/nifi-redis-bundle/nifi-redis-extensions/src/main/java/org/apache/nifi/redis/service/RedisDistributedMapCacheClientService.java b/nifi-nar-bundles/nifi-redis-bundle/nifi-redis-extensions/src/main/java/org/apache/nifi/redis/service/RedisDistributedMapCacheClientService.java
index 45ceef2..7fd6c9b 100644
--- a/nifi-nar-bundles/nifi-redis-bundle/nifi-redis-extensions/src/main/java/org/apache/nifi/redis/service/RedisDistributedMapCacheClientService.java
+++ b/nifi-nar-bundles/nifi-redis-bundle/nifi-redis-extensions/src/main/java/org/apache/nifi/redis/service/RedisDistributedMapCacheClientService.java
@@ -161,8 +161,9 @@
                 final List<Object> results = redisConnection.exec();
 
                 // if the results list was empty, then the transaction failed (i.e. key was modified after we started watching), so keep looping to retry
+                // if the results list was null, then the transaction failed
                 // if the results list has results, then the transaction succeeded and it should have the result of the setNX operation
-                if (results.size() > 0) {
+                if (results != null && results.size() > 0) {
                     final Object firstResult = results.get(0);
                     if (firstResult instanceof Boolean) {
                         final Boolean absent = (Boolean) firstResult;
@@ -337,7 +338,7 @@
             final List<Object> results = redisConnection.exec();
 
             // if we have a result then the replace succeeded
-            if (results.size() > 0) {
+            if (results != null && results.size() > 0) {
                 replaced = true;
             }