[SPARK-14940][SQL] Move ExternalCatalog to own file

## What changes were proposed in this pull request?

`interfaces.scala` was getting big. This just moves the biggest class in there to a new file for cleanliness.

## How was this patch tested?

Just moving things around.

Author: Andrew Or <andrew@databricks.com>

Closes #12721 from andrewor14/move-external-catalog.

4 files changed, 6 insertions, 5 deletions

diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/commands.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/commands.scala
index 855e7e2fe3..5f9287b3b5 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/commands.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/commands.scala
@@ -23,7 +23,7 @@ import org.apache.spark.rdd.RDD
 import org.apache.spark.sql.{AnalysisException, Row, SparkSession}
 import org.apache.spark.sql.catalyst.{CatalystTypeConverters, InternalRow, TableIdentifier}
 import org.apache.spark.sql.catalyst.catalog.CatalogTableType
-import org.apache.spark.sql.catalyst.catalog.ExternalCatalog.TablePartitionSpec
+import org.apache.spark.sql.catalyst.catalog.CatalogTypes.TablePartitionSpec
 import org.apache.spark.sql.catalyst.errors.TreeNodeException
 import org.apache.spark.sql.catalyst.expressions.{Attribute, AttributeReference}
 import org.apache.spark.sql.catalyst.plans.logical
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/ddl.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/ddl.scala
index 4a9a1603d0..44647116b4 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/ddl.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/ddl.scala
@@ -24,7 +24,7 @@ import org.apache.spark.sql.{AnalysisException, Row, SparkSession}
 import org.apache.spark.sql.catalyst.TableIdentifier
 import org.apache.spark.sql.catalyst.catalog.{CatalogDatabase, CatalogTable}
 import org.apache.spark.sql.catalyst.catalog.{CatalogTablePartition, CatalogTableType, SessionCatalog}
-import org.apache.spark.sql.catalyst.catalog.ExternalCatalog.TablePartitionSpec
+import org.apache.spark.sql.catalyst.catalog.CatalogTypes.TablePartitionSpec
 import org.apache.spark.sql.catalyst.expressions.{Attribute, AttributeReference}
 import org.apache.spark.sql.catalyst.parser.ParseException
 import org.apache.spark.sql.types._
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/tables.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/tables.scala
index f38e260bc9..6078918316 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/tables.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/tables.scala
@@ -24,7 +24,8 @@ import scala.collection.mutable.ArrayBuffer
 
 import org.apache.spark.sql.{AnalysisException, Row, SparkSession}
 import org.apache.spark.sql.catalyst.TableIdentifier
-import org.apache.spark.sql.catalyst.catalog.{CatalogRelation, CatalogTable, CatalogTableType, ExternalCatalog}
+import org.apache.spark.sql.catalyst.catalog.{CatalogRelation, CatalogTable, CatalogTableType}
+import org.apache.spark.sql.catalyst.catalog.CatalogTypes.TablePartitionSpec
 import org.apache.spark.sql.catalyst.expressions.{Attribute, AttributeReference}
 import org.apache.spark.sql.catalyst.plans.logical.{Command, LogicalPlan, UnaryNode}
 import org.apache.spark.sql.types.{BooleanType, MetadataBuilder, StringType}
@@ -156,7 +157,7 @@ case class LoadData(
     path: String,
     isLocal: Boolean,
     isOverwrite: Boolean,
-    partition: Option[ExternalCatalog.TablePartitionSpec]) extends RunnableCommand {
+    partition: Option[TablePartitionSpec]) extends RunnableCommand {
 
   override def run(sparkSession: SparkSession): Seq[Row] = {
     val catalog = sparkSession.sessionState.catalog
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala
index 58330c49c7..a9a9bf76be 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala
@@ -26,7 +26,7 @@ import org.apache.spark.sql.catalyst.TableIdentifier
 import org.apache.spark.sql.catalyst.catalog.{CatalogDatabase, CatalogStorageFormat}
 import org.apache.spark.sql.catalyst.catalog.{CatalogTable, CatalogTableType}
 import org.apache.spark.sql.catalyst.catalog.{CatalogTablePartition, SessionCatalog}
-import org.apache.spark.sql.catalyst.catalog.ExternalCatalog.TablePartitionSpec
+import org.apache.spark.sql.catalyst.catalog.CatalogTypes.TablePartitionSpec
 import org.apache.spark.sql.test.SharedSQLContext
 
 class DDLSuite extends QueryTest with SharedSQLContext with BeforeAndAfterEach {