[SPARK-11595][SQL][BRANCH-1.5] Fixes ADD JAR when the input path contains URL scheme

This PR backports #9569 to branch-1.5.

Author: Cheng Lian <lian@databricks.com>

Closes #9570 from liancheng/spark-11595.for-branch-1.5.

Author: liancheng

sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/commands.scala

@@ -17,6 +17,9 @@
 
 package org.apache.spark.sql.hive.execution
 
+import java.io.File
+
+import org.apache.hadoop.fs.Path
 import org.apache.hadoop.hive.metastore.MetaStoreUtils
 import org.apache.spark.sql._
 import org.apache.spark.sql.catalyst.{TableIdentifier, SqlParser}
@@ -90,7 +93,17 @@ case class AddJar(path: String) extends RunnableCommand {
     val currentClassLoader = Utils.getContextOrSparkClassLoader
 
     // Add jar to current context
-    val jarURL = new java.io.File(path).toURI.toURL
+    val jarURL = {
+      val uri = new Path(path).toUri
+      if (uri.getScheme == null) {
+        // `path` is a local file path without a URL scheme
+        new File(path).toURI.toURL
+      } else {
+        // `path` is a URL with a scheme
+        uri.toURL
+      }
+    }
+
     val newClassLoader = new java.net.URLClassLoader(Array(jarURL), currentClassLoader)
     Thread.currentThread.setContextClassLoader(newClassLoader)
     // We need to explicitly set the class loader associated with the conf in executionHive's

sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala

@@ -70,7 +70,12 @@ class SQLQuerySuite extends QueryTest with SQLTestUtils {
   private val sqlContext = _sqlContext
 
   test("UDTF") {
-    sql(s"ADD JAR ${TestHive.getHiveFile("TestUDTF.jar").getCanonicalPath()}")
+    val jarPath = TestHive.getHiveFile("TestUDTF.jar").getCanonicalPath
+
+    // SPARK-11595 Fixes ADD JAR when input path contains URL scheme
+    val jarURL = s"file://$jarPath"
+
+    sql(s"ADD JAR $jarURL")
     // The function source code can be found at:
     // https://cwiki.apache.org/confluence/display/Hive/DeveloperGuide+UDTF
     sql(