HDFS-16194. Simplify the code with DatanodeID#getXferAddrWithHostname (#3354). Contributed by tomscut.

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/metrics/NamenodeBeanMetrics.java

@@ -484,7 +484,7 @@ public class NamenodeBeanMetrics
         innerinfo.put("blockPoolUsed", node.getBlockPoolUsed());
         innerinfo.put("blockPoolUsedPercent", node.getBlockPoolUsedPercent());
         innerinfo.put("volfails", -1); // node.getVolumeFailures()
-        info.put(node.getHostName() + ":" + node.getXferPort(),
+        info.put(node.getXferAddrWithHostname(),
             Collections.unmodifiableMap(innerinfo));
       }
     } catch (StandbyException e) {

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -1815,10 +1815,9 @@ public class DataNode extends ReconfigurableBase
   }
 
   /**
-   * @return name useful for logging
+   * @return name useful for logging or display
    */
   public String getDisplayName() {
-    // NB: our DatanodeID may not be set yet
     return hostName + ":" + getXferPort();
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -6537,7 +6537,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       if (node.getUpgradeDomain() != null) {
         innerinfo.put("upgradeDomain", node.getUpgradeDomain());
       }
-      info.put(node.getHostName() + ":" + node.getXferPort(), innerinfo.build());
+      info.put(node.getXferAddrWithHostname(), innerinfo.build());
     }
     return JSON.toString(info);
   }
@@ -6560,7 +6560,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
           .put("xferaddr", node.getXferAddr())
           .put("location", node.getNetworkLocation())
           .build();
-      info.put(node.getHostName() + ":" + node.getXferPort(), innerinfo);
+      info.put(node.getXferAddrWithHostname(), innerinfo);
     }
     return JSON.toString(info);
   }
@@ -6588,7 +6588,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
           .put("underReplicateInOpenFiles",
           node.getLeavingServiceStatus().getUnderReplicatedInOpenFiles())
           .build();
-      info.put(node.getHostName() + ":" + node.getXferPort(), innerinfo);
+      info.put(node.getXferAddrWithHostname(), innerinfo);
     }
     return JSON.toString(info);
   }
@@ -6616,7 +6616,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
           .put("underReplicateInOpenFiles",
               node.getLeavingServiceStatus().getUnderReplicatedInOpenFiles())
           .build();
-      nodesMap.put(node.getHostName() + ":" + node.getXferPort(), attrMap);
+      nodesMap.put(node.getXferAddrWithHostname(), attrMap);
     }
     return JSON.toString(nodesMap);
   }