From eedd976c6e65d000adebf121e8ce97873ff2f2d3 Mon Sep 17 00:00:00 2001
From: stack <stack@apache.org>
Date: Sun, 20 Dec 2020 20:25:09 -0800
Subject: [PATCH] HBASE-25425 Some notes on RawCell

---
 .../java/org/apache/hadoop/hbase/client/Mutation.java  | 10 ----------
 .../src/main/java/org/apache/hadoop/hbase/RawCell.java |  6 +++++-
 2 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
index de85ddd9759..d49b7257e50 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
@@ -40,7 +40,6 @@ import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.IndividualBytesFieldCell;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.PrivateCellUtil;
-import org.apache.hadoop.hbase.RawCell;
 import org.apache.hadoop.hbase.Tag;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.io.HeapSize;
@@ -932,25 +931,16 @@ public abstract class Mutation extends OperationWithAttributes implements Row, C
 
     @Override
     public Optional<Tag> getTag(byte type) {
-      if (cell instanceof RawCell) {
-        return ((RawCell) cell).getTag(type);
-      }
       return PrivateCellUtil.getTag(cell, type);
     }
 
     @Override
     public Iterator<Tag> getTags() {
-      if (cell instanceof RawCell) {
-        return ((RawCell) cell).getTags();
-      }
       return PrivateCellUtil.tagsIterator(cell);
     }
 
     @Override
     public byte[] cloneTags() {
-      if (cell instanceof RawCell) {
-        return ((RawCell) cell).cloneTags();
-      }
       return PrivateCellUtil.cloneTags(cell);
     }
 
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/RawCell.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/RawCell.java
index 85f8b278de4..d29e8ca8bdc 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/RawCell.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/RawCell.java
@@ -24,8 +24,12 @@ import java.util.Optional;
 import org.apache.yetus.audience.InterfaceAudience;
 
 /**
- * An extended version of cell that gives more power to CPs
+ * An extended version of Cell that allows CPs manipulate Tags.
  */
+// Added by HBASE-19092 to expose Tags to CPs (history server) w/o exposing ExtendedCell.
+// Why is this in hbase-common and not in hbase-server where it is used?
+// RawCell is an odd name for a class that is only for CPs that want to manipulate Tags on
+// server-side only w/o exposing ExtendedCell -- super rare, super exotic.
 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.COPROC)
 public interface RawCell extends Cell {
   static final int MAX_TAGS_LENGTH = (2 * Short.MAX_VALUE) + 1;