[SPARK-18703][SQL] Drop Staging Directories and Data Files After each Insertion/CTAS of Hive serde Tables

### What changes were proposed in this pull request?
Below are the files/directories generated for three inserts againsts a Hive table:
```
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-29_149_4298858301766472202-1
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-29_149_4298858301766472202-1/-ext-10000
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-29_149_4298858301766472202-1/-ext-10000/._SUCCESS.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-29_149_4298858301766472202-1/-ext-10000/.part-00000.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-29_149_4298858301766472202-1/-ext-10000/_SUCCESS
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-29_149_4298858301766472202-1/-ext-10000/part-00000
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_454_6445008511655931341-1
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_454_6445008511655931341-1/-ext-10000
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_454_6445008511655931341-1/-ext-10000/._SUCCESS.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_454_6445008511655931341-1/-ext-10000/.part-00000.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_454_6445008511655931341-1/-ext-10000/_SUCCESS
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_454_6445008511655931341-1/-ext-10000/part-00000
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_722_3388423608658711001-1
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_722_3388423608658711001-1/-ext-10000
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_722_3388423608658711001-1/-ext-10000/._SUCCESS.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_722_3388423608658711001-1/-ext-10000/.part-00000.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_722_3388423608658711001-1/-ext-10000/_SUCCESS
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.hive-staging_hive_2016-12-03_20-56-30_722_3388423608658711001-1/-ext-10000/part-00000
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.part-00000.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/part-00000
```

The first 18 files are temporary. We do not drop it until the end of JVM termination. If JVM does not appropriately terminate, these temporary files/directories will not be dropped.

Only the last two files are needed, as shown below.
```
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/.part-00000.crc
/private/var/folders/4b/sgmfldk15js406vk7lw5llzw0000gn/T/spark-41eaa5ce-0288-471e-bba1-09cc482813ff/part-00000
```
The temporary files/directories could accumulate a lot when we issue many inserts, since each insert generats at least six files. This could eat a lot of spaces and slow down the JVM termination. When the JVM does not terminates approprately, the files might not be dropped.

This PR is to drop the created staging files and temporary data files after each insert/CTAS.

### How was this patch tested?
Added a test case

Author: gatorsmile <gatorsmile@gmail.com>

Closes #16134 from gatorsmile/deleteFiles.

1 files changed, 24 insertions, 0 deletions

diff --git a/sql/hive/src/test/scala/org/apache/spark/sql/hive/client/VersionsSuite.scala b/sql/hive/src/test/scala/org/apache/spark/sql/hive/client/VersionsSuite.scala
index 9b26383a16..8dd06998ba 100644
--- a/sql/hive/src/test/scala/org/apache/spark/sql/hive/client/VersionsSuite.scala
+++ b/sql/hive/src/test/scala/org/apache/spark/sql/hive/client/VersionsSuite.scala
@@ -546,6 +546,30 @@ class VersionsSuite extends SparkFunSuite with SQLTestUtils with TestHiveSinglet
       }
     }
 
+    test(s"$version: Delete the temporary staging directory and files after each insert") {
+      withTempDir { tmpDir =>
+        withTable("tab") {
+          spark.sql(
+            s"""
+               |CREATE TABLE tab(c1 string)
+               |location '${tmpDir.toURI.toString}'
+             """.stripMargin)
+
+          (1 to 3).map { i =>
+            spark.sql(s"INSERT OVERWRITE TABLE tab SELECT '$i'")
+          }
+          def listFiles(path: File): List[String] = {
+            val dir = path.listFiles()
+            val folders = dir.filter(_.isDirectory).toList
+            val filePaths = dir.map(_.getName).toList
+            folders.flatMap(listFiles) ++: filePaths
+          }
+          val expectedFiles = ".part-00000.crc" :: "part-00000" :: Nil
+          assert(listFiles(tmpDir).sorted == expectedFiles)
+        }
+      }
+    }
+
     // TODO: add more tests.
   }
 }