diff --git a/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala b/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala
index 300ae4339c3c43d21bff53a858fe24ce0b85e19c..1943a4a7475f5fbc4f832175644044aebb9d56a5 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala
@@ -32,7 +32,7 @@ import org.apache.spark.mllib.regression.LabeledPoint
 import org.apache.spark.mllib.tree.configuration.{Algo => OldAlgo, Strategy => OldStrategy}
 import org.apache.spark.mllib.tree.model.{DecisionTreeModel => OldDecisionTreeModel}
 import org.apache.spark.rdd.RDD
-import org.apache.spark.sql.{DataFrame, Dataset}
+import org.apache.spark.sql.Dataset
 
 
 /**
diff --git a/mllib/src/main/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifier.scala b/mllib/src/main/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifier.scala
index 456e22de91b1c224658203df47a1f67f1286f51e..72cf55f6bb99750e03a486e95db0ae9471529624 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifier.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifier.scala
@@ -29,7 +29,7 @@ import org.apache.spark.ml.param.shared.{HasMaxIter, HasSeed, HasStepSize, HasTo
 import org.apache.spark.ml.util._
 import org.apache.spark.mllib.linalg.{Vector, Vectors}
 import org.apache.spark.mllib.regression.LabeledPoint
-import org.apache.spark.sql.{DataFrame, Dataset}
+import org.apache.spark.sql.Dataset
 
 /** Params for Multilayer Perceptron. */
 private[ml] trait MultilayerPerceptronParams extends PredictorParams
diff --git a/mllib/src/main/scala/org/apache/spark/ml/evaluation/RegressionEvaluator.scala b/mllib/src/main/scala/org/apache/spark/ml/evaluation/RegressionEvaluator.scala
index ed04b67bcc93b660a971335de63c6bc17a52ddce..988f6e918f64f76a6dda503f953e54536a382d53 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/evaluation/RegressionEvaluator.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/evaluation/RegressionEvaluator.scala
@@ -22,7 +22,7 @@ import org.apache.spark.ml.param.{Param, ParamMap, ParamValidators}
 import org.apache.spark.ml.param.shared.{HasLabelCol, HasPredictionCol}
 import org.apache.spark.ml.util.{DefaultParamsReadable, DefaultParamsWritable, Identifiable}
 import org.apache.spark.mllib.evaluation.RegressionMetrics
-import org.apache.spark.sql.{DataFrame, Dataset, Row}
+import org.apache.spark.sql.{Dataset, Row}
 import org.apache.spark.sql.functions._
 import org.apache.spark.sql.types.{DoubleType, FloatType}
 
diff --git a/mllib/src/main/scala/org/apache/spark/ml/feature/QuantileDiscretizer.scala b/mllib/src/main/scala/org/apache/spark/ml/feature/QuantileDiscretizer.scala
index 5c7993af645af9b157d839e3eb5c43da8070d75d..5a6daa06ef546c5f85eef0c28797c1aa03faaec0 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/feature/QuantileDiscretizer.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/feature/QuantileDiscretizer.scala
@@ -17,8 +17,6 @@
 
 package org.apache.spark.ml.feature
 
-import scala.collection.mutable
-
 import org.apache.spark.annotation.{Experimental, Since}
 import org.apache.spark.internal.Logging
 import org.apache.spark.ml._
@@ -26,9 +24,8 @@ import org.apache.spark.ml.attribute.NominalAttribute
 import org.apache.spark.ml.param._
 import org.apache.spark.ml.param.shared.{HasInputCol, HasOutputCol, HasSeed}
 import org.apache.spark.ml.util._
-import org.apache.spark.sql.{Dataset, Row}
+import org.apache.spark.sql.Dataset
 import org.apache.spark.sql.types.{DoubleType, StructType}
-import org.apache.spark.util.random.XORShiftRandom
 
 /**
  * Params for [[QuantileDiscretizer]].
diff --git a/mllib/src/main/scala/org/apache/spark/ml/tree/impl/NodeIdCache.scala b/mllib/src/main/scala/org/apache/spark/ml/tree/impl/NodeIdCache.scala
index 9d697a36b67dac545a0ee769e04e800020d0a4ef..800430f96c5b132af9db10e62231f393971da5c0 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/tree/impl/NodeIdCache.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/tree/impl/NodeIdCache.scala
@@ -23,7 +23,6 @@ import scala.collection.mutable
 
 import org.apache.hadoop.fs.{FileSystem, Path}
 
-import org.apache.spark.annotation.DeveloperApi
 import org.apache.spark.internal.Logging
 import org.apache.spark.ml.tree.{LearningNode, Split}
 import org.apache.spark.rdd.RDD
diff --git a/mllib/src/test/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifierSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifierSuite.scala
index 80547fad6af8db891b37e138b1cca06565d1052e..f41db31f1e7e20a4ec77ece778740d5fde822011 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifierSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/classification/MultilayerPerceptronClassifierSuite.scala
@@ -26,7 +26,7 @@ import org.apache.spark.mllib.evaluation.MulticlassMetrics
 import org.apache.spark.mllib.linalg.{Vector, Vectors}
 import org.apache.spark.mllib.util.MLlibTestSparkContext
 import org.apache.spark.mllib.util.TestingUtils._
-import org.apache.spark.sql.{DataFrame, Dataset, Row}
+import org.apache.spark.sql.{Dataset, Row}
 
 class MultilayerPerceptronClassifierSuite
   extends SparkFunSuite with MLlibTestSparkContext with DefaultReadWriteTest {
diff --git a/mllib/src/test/scala/org/apache/spark/ml/classification/OneVsRestSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/classification/OneVsRestSuite.scala
index f3e8fd11b296a31b8eaf654e9043632b02f98f58..51871a9babe45244df0b1fff72e4012b12566f8d 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/classification/OneVsRestSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/classification/OneVsRestSuite.scala
@@ -30,7 +30,7 @@ import org.apache.spark.mllib.regression.LabeledPoint
 import org.apache.spark.mllib.util.MLlibTestSparkContext
 import org.apache.spark.mllib.util.TestingUtils._
 import org.apache.spark.rdd.RDD
-import org.apache.spark.sql.{DataFrame, Dataset}
+import org.apache.spark.sql.Dataset
 import org.apache.spark.sql.types.Metadata
 
 class OneVsRestSuite extends SparkFunSuite with MLlibTestSparkContext with DefaultReadWriteTest {
diff --git a/mllib/src/test/scala/org/apache/spark/ml/clustering/BisectingKMeansSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/clustering/BisectingKMeansSuite.scala
index e641d79c1707b415278b86f2fb38219d46bfbf12..212ea7a0a960f33b2a236572c0f54c78549ffcb0 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/clustering/BisectingKMeansSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/clustering/BisectingKMeansSuite.scala
@@ -20,7 +20,7 @@ package org.apache.spark.ml.clustering
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.ml.util.DefaultReadWriteTest
 import org.apache.spark.mllib.util.MLlibTestSparkContext
-import org.apache.spark.sql.{DataFrame, Dataset}
+import org.apache.spark.sql.Dataset
 
 class BisectingKMeansSuite
   extends SparkFunSuite with MLlibTestSparkContext with DefaultReadWriteTest {
diff --git a/mllib/src/test/scala/org/apache/spark/ml/clustering/GaussianMixtureSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/clustering/GaussianMixtureSuite.scala
index 1a274aea291f487cd5dc4d549ee81d251c6a30c5..df6bb411d5f284ece2537343d6a069b2099cab6e 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/clustering/GaussianMixtureSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/clustering/GaussianMixtureSuite.scala
@@ -20,7 +20,7 @@ package org.apache.spark.ml.clustering
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.ml.util.DefaultReadWriteTest
 import org.apache.spark.mllib.util.MLlibTestSparkContext
-import org.apache.spark.sql.{DataFrame, Dataset}
+import org.apache.spark.sql.Dataset
 
 
 class GaussianMixtureSuite extends SparkFunSuite with MLlibTestSparkContext
diff --git a/mllib/src/test/scala/org/apache/spark/ml/feature/NGramSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/feature/NGramSuite.scala
index e4e15f43310ba9ea814fffabfd60bfe827f748e4..a9421e682519d8214f2ba63dcfb04d621e6ed669 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/feature/NGramSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/feature/NGramSuite.scala
@@ -22,7 +22,7 @@ import scala.beans.BeanInfo
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.ml.util.DefaultReadWriteTest
 import org.apache.spark.mllib.util.MLlibTestSparkContext
-import org.apache.spark.sql.{DataFrame, Dataset, Row}
+import org.apache.spark.sql.{Dataset, Row}
 
 @BeanInfo
 case class NGramTestData(inputTokens: Array[String], wantedNGrams: Array[String])
diff --git a/mllib/src/test/scala/org/apache/spark/ml/feature/TokenizerSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/feature/TokenizerSuite.scala
index 299f6223b20b7876f2e8c402c338b2400cb3ad57..123ddfe42c958b0541184b41ab0d91dc65b033cf 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/feature/TokenizerSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/feature/TokenizerSuite.scala
@@ -23,7 +23,7 @@ import org.apache.spark.SparkFunSuite
 import org.apache.spark.ml.param.ParamsSuite
 import org.apache.spark.ml.util.DefaultReadWriteTest
 import org.apache.spark.mllib.util.MLlibTestSparkContext
-import org.apache.spark.sql.{DataFrame, Dataset, Row}
+import org.apache.spark.sql.{Dataset, Row}
 
 @BeanInfo
 case class TokenizerTestData(rawText: String, wantedTokens: Array[String])
diff --git a/mllib/src/test/scala/org/apache/spark/ml/util/DefaultReadWriteTest.scala b/mllib/src/test/scala/org/apache/spark/ml/util/DefaultReadWriteTest.scala
index 7ebd7eb144632ce4b837b22ae4907862ae3969a4..553b8725b30a31f4f232ef042f6adfbe56dce30f 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/util/DefaultReadWriteTest.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/util/DefaultReadWriteTest.scala
@@ -25,7 +25,7 @@ import org.apache.spark.SparkFunSuite
 import org.apache.spark.ml.{Estimator, Model}
 import org.apache.spark.ml.param._
 import org.apache.spark.mllib.util.MLlibTestSparkContext
-import org.apache.spark.sql.{DataFrame, Dataset}
+import org.apache.spark.sql.Dataset
 
 trait DefaultReadWriteTest extends TempDirectory { self: Suite =>
 
diff --git a/mllib/src/test/scala/org/apache/spark/mllib/util/MLlibTestSparkContext.scala b/mllib/src/test/scala/org/apache/spark/mllib/util/MLlibTestSparkContext.scala
index cb1efd525134a5d2351539a5784f6cd581c7cbe1..7f9e340f54b692a13f082b9cd5d82d753d857282 100644
--- a/mllib/src/test/scala/org/apache/spark/mllib/util/MLlibTestSparkContext.scala
+++ b/mllib/src/test/scala/org/apache/spark/mllib/util/MLlibTestSparkContext.scala
@@ -19,7 +19,6 @@ package org.apache.spark.mllib.util
 
 import java.io.File
 
-import org.apache.hadoop.fs.Path
 import org.scalatest.Suite
 
 import org.apache.spark.{SparkConf, SparkContext}
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 11612c20d0df986a25f32ca3ea82833707600586..b7e3056f92f61374a1677f42e98ab34176c1c5a3 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 +24,7 @@ import scala.collection.mutable.ArrayBuffer
 
 import org.apache.spark.sql.{AnalysisException, Row, SQLContext}
 import org.apache.spark.sql.catalyst.TableIdentifier
-import org.apache.spark.sql.catalyst.catalog.{CatalogRelation, CatalogTable, CatalogTableType, ExternalCatalog, SimpleCatalogRelation}
+import org.apache.spark.sql.catalyst.catalog.{CatalogRelation, CatalogTable, CatalogTableType, ExternalCatalog}
 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.{MetadataBuilder, StringType}
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/InsertIntoHadoopFsRelation.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/InsertIntoHadoopFsRelation.scala
index 889c0204f8e6c85f087f700152769a9f19c87d10..95629a9923cd3c0da5ad415e11d2015903a034c5 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/InsertIntoHadoopFsRelation.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/InsertIntoHadoopFsRelation.scala
@@ -31,7 +31,6 @@ import org.apache.spark.sql.catalyst.InternalRow
 import org.apache.spark.sql.execution.SQLExecution
 import org.apache.spark.sql.execution.command.RunnableCommand
 import org.apache.spark.sql.internal.SQLConf
-import org.apache.spark.sql.sources._
 
 /**
  * A command for writing data to a [[HadoopFsRelation]].  Supports both overwriting and appending.
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/ShuffledHashJoinExec.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/ShuffledHashJoinExec.scala
index 68cd3cb49c1609badccaa97d98a6f269d5abdfd9..a242a078f608105e96291132d2bbe6fe047f04ff 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/ShuffledHashJoinExec.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/ShuffledHashJoinExec.scala
@@ -20,7 +20,7 @@ package org.apache.spark.sql.execution.joins
 import org.apache.spark.TaskContext
 import org.apache.spark.rdd.RDD
 import org.apache.spark.sql.catalyst.InternalRow
-import org.apache.spark.sql.catalyst.expressions.{BindReferences, Expression, UnsafeRow}
+import org.apache.spark.sql.catalyst.expressions.Expression
 import org.apache.spark.sql.catalyst.plans._
 import org.apache.spark.sql.catalyst.plans.physical._
 import org.apache.spark.sql.execution.{BinaryExecNode, SparkPlan}
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/python/EvaluatePython.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/python/EvaluatePython.scala
index 3b05e29e52bd3f45bd81bb0ae20b67465a4c5a9b..cf68ed4ec36a8a6a4e12b432032b268f7122d1a0 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/python/EvaluatePython.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/python/EvaluatePython.scala
@@ -29,8 +29,6 @@ import org.apache.spark.rdd.RDD
 import org.apache.spark.sql.DataFrame
 import org.apache.spark.sql.catalyst.InternalRow
 import org.apache.spark.sql.catalyst.expressions._
-import org.apache.spark.sql.catalyst.plans.logical
-import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan
 import org.apache.spark.sql.catalyst.util.{ArrayBasedMapData, ArrayData, GenericArrayData, MapData}
 import org.apache.spark.sql.types._
 import org.apache.spark.unsafe.types.UTF8String