Address comments

Author: dongjoon-hyun

sql/core/src/main/scala/org/apache/spark/sql/internal/SharedState.scala

@@ -36,6 +36,7 @@ import org.apache.spark.sql.execution.CacheManager
 import org.apache.spark.sql.execution.streaming.StreamExecution
 import org.apache.spark.sql.execution.ui.{SQLAppStatusListener, SQLAppStatusStore, SQLTab}
 import org.apache.spark.sql.internal.StaticSQLConf._
+import org.apache.spark.sql.internal.config.DEFAULT_URL_STREAM_HANDLER_FACTORY_ENABLED
 import org.apache.spark.sql.streaming.StreamingQuery
 import org.apache.spark.status.ElementTrackingStore
 import org.apache.spark.util.Utils
@@ -202,7 +203,7 @@ object SharedState extends Logging {
           "so it can not be modified")
       case None => synchronized {
         try {
-          if (conf.getBoolean("spark.fsUrlStreamHandlerFactory.enabled", true)) {
+          if (conf.get(DEFAULT_URL_STREAM_HANDLER_FACTORY_ENABLED)) {
             URL.setURLStreamHandlerFactory(defaultFactory)
             factory = Some(defaultFactory)
           }

sql/core/src/main/scala/org/apache/spark/sql/internal/config/package.scala

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.internal
+
+import org.apache.spark.internal.config.ConfigBuilder
+
+package object config {
+
+  private[spark] val DEFAULT_URL_STREAM_HANDLER_FACTORY_ENABLED =
+    ConfigBuilder("spark.sql.defaultUrlStreamHandlerFactory.enabled")
+      .doc("When true, set FsUrlStreamHandlerFactory to support ADD JAR against HDFS locations")
+      .booleanConf
+      .createWithDefault(true)
+}