From f8bbc92358209498f219a14a4eea99c8563c22e8 Mon Sep 17 00:00:00 2001
From: Nick Dimiduk <ndimiduk@apache.org>
Date: Fri, 13 Jan 2023 15:29:20 +0100
Subject: [PATCH] PR feedback

---
 .../actions/DumpHdfsClusterStatusAction.java  |  2 +-
 .../actions/RestartActiveNameNodeAction.java  | 32 +++++++++++--------
 2 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/DumpHdfsClusterStatusAction.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/DumpHdfsClusterStatusAction.java
index 88c2aea65058..932590f84b23 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/DumpHdfsClusterStatusAction.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/DumpHdfsClusterStatusAction.java
@@ -73,6 +73,6 @@ public void perform() throws Exception {
     }
     // TODO: add more on NN, JNs, and ZK.
     // TODO: Print how long process has been up.
-    LOG.info(sb.toString());
+    getLogger().info(sb.toString());
   }
 }
diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/RestartActiveNameNodeAction.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/RestartActiveNameNodeAction.java
index 178a4ab067e6..13e67b8e7eed 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/RestartActiveNameNodeAction.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/RestartActiveNameNodeAction.java
@@ -17,7 +17,9 @@
  */
 package org.apache.hadoop.hbase.chaos.actions;
 
+import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.zookeeper.RecoverableZooKeeper;
@@ -78,26 +80,30 @@ public void perform() throws Exception {
         final String hadoopHAZkNodePath = ZNodePaths.joinZNode(
           (hadoopHAZkNode != null && hadoopHAZkNode.equals("/")) ? "" : hadoopHAZkNode,
           nameServiceID);
-        final List<String> subChildren = ZKUtil.listChildrenNoWatch(zkw, hadoopHAZkNodePath);
+        final List<String> subChildren =
+          Optional.ofNullable(ZKUtil.listChildrenNoWatch(zkw, hadoopHAZkNodePath))
+            .orElse(Collections.emptyList());
         for (final String eachEntry : subChildren) {
-          if (eachEntry.contains(ACTIVE_NN_LOCK_NAME)) {
-            byte[] data = rzk.getData(ZNodePaths.joinZNode(hadoopHAZkNodePath, ACTIVE_NN_LOCK_NAME),
-              false, null);
-            ActiveNodeInfo proto = ActiveNodeInfo.parseFrom(data);
-            activeNamenode = proto.getHostname();
-            activeNamenodePort = proto.getPort();
+          if (!eachEntry.contains(ACTIVE_NN_LOCK_NAME)) {
+            continue;
           }
+          byte[] data =
+            rzk.getData(ZNodePaths.joinZNode(hadoopHAZkNodePath, ACTIVE_NN_LOCK_NAME), false, null);
+          ActiveNodeInfo proto = ActiveNodeInfo.parseFrom(data);
+          activeNamenode = proto.getHostname();
+          activeNamenodePort = proto.getPort();
         }
       }
     }
 
     if (activeNamenode == null) {
-      throw new Exception("No active Name node found in zookeeper under " + hadoopHAZkNode);
-    } else {
-      getLogger().info("Found Active NameNode host: {}", activeNamenode);
-      final ServerName activeNNHost = ServerName.valueOf(activeNamenode, activeNamenodePort, -1L);
-      getLogger().info("Restarting Active NameNode: {}", activeNamenode);
-      restartNameNode(activeNNHost, this.sleepTime);
+      getLogger().info("No active Name node found in zookeeper under '{}'", hadoopHAZkNode);
+      return;
     }
+
+    getLogger().info("Found Active NameNode host: {}", activeNamenode);
+    final ServerName activeNNHost = ServerName.valueOf(activeNamenode, activeNamenodePort, -1L);
+    getLogger().info("Restarting Active NameNode: {}", activeNamenode);
+    restartNameNode(activeNNHost, this.sleepTime);
   }
 }