From 6a1fba9ce862895a4ca0836a855b9bce6189e5df Mon Sep 17 00:00:00 2001
From: Yutong Sean <yutongsean@gmail.com>
Date: Thu, 20 Jan 2022 11:46:33 +0800
Subject: [PATCH 1/2] HBASE-26688 Result#advance, current are not thread safe.
 But the pre-created EMPTY_RESULT like objects can be shared by multi client
 threads.

---
 .../src/main/java/org/apache/hadoop/hbase/client/Result.java  | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
index bff50338ba5f..7c4d9dd7528b 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
@@ -913,7 +913,7 @@ public CellScanner cellScanner() {
 
   @Override
   public Cell current() {
-    if (cells == null
+    if (isEmpty()
             || cellScannerIndex == INITIAL_CELLSCANNER_INDEX
             || cellScannerIndex >= cells.length)
       return null;
@@ -922,7 +922,7 @@ public Cell current() {
 
   @Override
   public boolean advance() {
-    if (cells == null) return false;
+    if (isEmpty()) return false;
     cellScannerIndex++;
     if (cellScannerIndex < this.cells.length) {
       return true;

From 917bd91b30b878d589535446f1b1e09f0402fa29 Mon Sep 17 00:00:00 2001
From: Yutong Sean <yutongsean@gmail.com>
Date: Thu, 20 Jan 2022 16:55:40 +0800
Subject: [PATCH 2/2] Checkstyle fix

---
 .../main/java/org/apache/hadoop/hbase/client/Result.java   | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
index 7c4d9dd7528b..b6c83f770b60 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
@@ -915,14 +915,17 @@ public CellScanner cellScanner() {
   public Cell current() {
     if (isEmpty()
             || cellScannerIndex == INITIAL_CELLSCANNER_INDEX
-            || cellScannerIndex >= cells.length)
+            || cellScannerIndex >= cells.length) {
       return null;
+    }
     return this.cells[cellScannerIndex];
   }
 
   @Override
   public boolean advance() {
-    if (isEmpty()) return false;
+    if (isEmpty()) {
+      return false;
+    }
     cellScannerIndex++;
     if (cellScannerIndex < this.cells.length) {
       return true;