YARN-3778. Fix Yarn resourcemanger CLI usage. Contributed by Brahma Reddy Battula

(cherry picked from commit 2b2465dfac1f147b6bb20d878b69a8cc3e85c8ad)

hadoop-yarn-project/CHANGES.txt

@@ -462,6 +462,8 @@ Release 2.8.0 - UNRELEASED
     YARN-3747. TestLocalDirsHandlerService should delete the created test directory logDir2.
     (David Moore via devaraj)
 
+    YARN-3778. Fix Yarn resourcemanger CLI usage. (Brahma Reddy Battula via xgong)
+
 Release 2.7.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/ResourceManager.java

@@ -1303,7 +1303,7 @@ public class ResourceManager extends CompositeService implements Recoverable {
   }
 
   private static void printUsage(PrintStream out) {
-    out.println("Usage: java ResourceManager [-format-state-store]");
+    out.println("Usage: yarn resourcemanager [-format-state-store]");
     out.println("                            "
         + "[-remove-application-from-state-store <appId>]" + "\n");
   }