From 5c988c99606080599534a751f061750f241c0945 Mon Sep 17 00:00:00 2001
From: tedyu <yuzhihong@gmail.com>
Date: Wed, 21 Feb 2018 13:05:54 -0800
Subject: [PATCH] HBASE-19166 AsyncProtobufLogWriter persists ProtobufLogWriter
 as class name for backward compatibility

---
 .../hbase/regionserver/wal/AsyncProtobufLogWriter.java   | 9 +++++++++
 .../regionserver/wal/SecureAsyncProtobufLogWriter.java   | 8 ++++++++
 2 files changed, 17 insertions(+)

diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java
index 67258ec0d62..abdc24e9c6e 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java
@@ -108,6 +108,15 @@ public class AsyncProtobufLogWriter extends AbstractProtobufLogWriter
     this.channelClass = channelClass;
   }
 
+  /*
+   * @return class name which is recognized by hbase-1.x to avoid ProtobufLogReader throwing error:
+   *   IOException: Got unknown writer class: AsyncProtobufLogWriter
+   */
+  @Override
+  protected String getWriterClassName() {
+    return "ProtobufLogWriter";
+  }
+
   @Override
   public void append(Entry entry) {
     int buffered = output.buffered();
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureAsyncProtobufLogWriter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureAsyncProtobufLogWriter.java
index 7741b5e274d..e2d294ac1f2 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureAsyncProtobufLogWriter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureAsyncProtobufLogWriter.java
@@ -38,6 +38,14 @@ public class SecureAsyncProtobufLogWriter extends AsyncProtobufLogWriter {
     super(eventLoopGroup, channelClass);
   }
 
+  /*
+   * @return class name which is recognized by hbase-1.x to avoid ProtobufLogReader throwing error:
+   *   IOException: Got unknown writer class: SecureAsyncProtobufLogWriter
+   */
+  @Override
+  protected String getWriterClassName() {
+    return "SecureProtobufLogWriter";
+  }
   @Override
   protected WALHeader buildWALHeader(Configuration conf, WALHeader.Builder builder)
       throws IOException {