YARN-10490. yarn top command not quitting completely with ctrl+c. Contributed by Agshin Kazimli

Author: szilard-nemeth

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/TopCLI.java

@@ -444,6 +444,7 @@ public TopCLI() throws IOException, InterruptedException {
 
   public static void main(String[] args) throws Exception {
     TopCLI topImp = new TopCLI();
+    topImp.addShutdownHook();
     topImp.setSysOutPrintStream(System.out);
     topImp.setSysErrPrintStream(System.err);
     int res = ToolRunner.run(topImp, args);
@@ -492,7 +493,6 @@ public int run(String[] args) throws Exception {
         rmStartTime = getRMStartTime();
       }
     }
-    clearScreen();
     return 0;
   }
 
@@ -1220,4 +1220,11 @@ private String getCommandOutput(String[] command) throws IOException,
     byte[] output = IOUtils.toByteArray(p.getInputStream());
     return new String(output, "ASCII");
   }
+
+  private void addShutdownHook() {
+    //clear screen when the program exits
+    Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+      clearScreen();
+    }));
+  }
 }