[SPARK-2970] [SQL] spark-sql script ends with IOException when EventL…

…ogging is enabled

Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>

Closes #1891 from sarutak/SPARK-2970 and squashes the following commits:

4a2d2fe [Kousuke Saruta] Modified comment style
8bd833c [Kousuke Saruta] Modified style
6c0997c [Kousuke Saruta] Modified the timing of shutdown hook execution. It should be executed before shutdown hook of o.a.h.f.FileSystem

(cherry picked from commit 905dc4b)
Signed-off-by: Michael Armbrust <michael@databricks.com>

sql/hive-thriftserver/src/main/scala/org/apache/spark/sql/hive/thriftserver/SparkSQLCLIDriver.scala

@@ -26,6 +26,8 @@ import jline.{ConsoleReader, History}
 import org.apache.commons.lang.StringUtils
 import org.apache.commons.logging.LogFactory
 import org.apache.hadoop.conf.Configuration
+import org.apache.hadoop.fs.FileSystem
+import org.apache.hadoop.util.ShutdownHookManager
 import org.apache.hadoop.hive.cli.{CliDriver, CliSessionState, OptionsProcessor}
 import org.apache.hadoop.hive.common.LogUtils.LogInitializationException
 import org.apache.hadoop.hive.common.{HiveInterruptCallback, HiveInterruptUtils, LogUtils}
@@ -116,13 +118,17 @@ private[hive] object SparkSQLCLIDriver {
     SessionState.start(sessionState)
 
     // Clean up after we exit
-    Runtime.getRuntime.addShutdownHook(
+    /**
+     * This should be executed before shutdown hook of
+     * FileSystem to avoid race condition of FileSystem operation
+     */
+    ShutdownHookManager.get.addShutdownHook(
       new Thread() {
         override def run() {
           SparkSQLEnv.stop()
         }
       }
-    )
+    , FileSystem.SHUTDOWN_HOOK_PRIORITY - 1)
 
     // "-h" option has been passed, so connect to Hive thrift server.
     if (sessionState.getHost != null) {