From 63392376c9edcd161dfa3cbdd1be5a18bbbfa0d0 Mon Sep 17 00:00:00 2001
From: Wei-Chiu Chuang <weichiu@apache.org>
Date: Tue, 18 May 2021 19:49:00 -0700
Subject: [PATCH] HDFS-16027. Replace abstract methods with default methods in
 JournalNodeMXBean. (#3018)

Reviewed-by: Ayush Saxena <ayushsaxena@apache.org>
---
 .../hdfs/qjournal/server/JournalNodeMXBean.java     | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/qjournal/server/JournalNodeMXBean.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/qjournal/server/JournalNodeMXBean.java
index f265c31a34..813a9e0a1f 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/qjournal/server/JournalNodeMXBean.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/qjournal/server/JournalNodeMXBean.java
@@ -20,6 +20,7 @@
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 
+import java.util.Collections;
 import java.util.List;
 
 /**
@@ -41,7 +42,9 @@ public interface JournalNodeMXBean {
    *
    * @return colon separated host and port.
    */
-  String getHostAndPort();
+  default String getHostAndPort() {
+    return "";
+  }
 
   /**
    * Get list of the clusters of JournalNode's journals
@@ -49,12 +52,16 @@ public interface JournalNodeMXBean {
    *
    * @return list of clusters.
    */
-  List<String> getClusterIds();
+  default List<String> getClusterIds() {
+    return Collections.emptyList() ;
+  }
 
   /**
    * Gets the version of Hadoop.
    *
    * @return the version of Hadoop.
    */
-  String getVersion();
+  default String getVersion() {
+    return "";
+  }
 }