[SPARK-22857] Optimize code by inspecting code

sql/core/src/main/java/org/apache/spark/sql/execution/datasources/parquet/VectorizedColumnReader.java

@@ -31,7 +31,6 @@
 import org.apache.parquet.schema.PrimitiveType;
 
 import org.apache.spark.sql.catalyst.util.DateTimeUtils;
-import org.apache.spark.sql.execution.vectorized.ColumnVector;
 import org.apache.spark.sql.execution.vectorized.WritableColumnVector;
 import org.apache.spark.sql.types.DataTypes;
 import org.apache.spark.sql.types.DecimalType;

sql/core/src/main/scala/org/apache/spark/sql/execution/LocalTableScanExec.scala

@@ -64,13 +64,13 @@ case class LocalTableScanExec(
   }
 
   override def executeCollect(): Array[InternalRow] = {
-    longMetric("numOutputRows").add(unsafeRows.size)
+    longMetric("numOutputRows").add(unsafeRows.length)
     unsafeRows
   }
 
   override def executeTake(limit: Int): Array[InternalRow] = {
     val taken = unsafeRows.take(limit)
-    longMetric("numOutputRows").add(taken.size)
+    longMetric("numOutputRows").add(taken.length)
     taken
   }
 }

sql/core/src/main/scala/org/apache/spark/sql/execution/arrow/ArrowWriter.scala

@@ -81,7 +81,7 @@ class ArrowWriter(val root: VectorSchemaRoot, fields: Array[ArrowFieldWriter]) {
 
   def write(row: InternalRow): Unit = {
     var i = 0
-    while (i < fields.size) {
+    while (i < fields.length) {
       fields(i).write(row, i)
       i += 1
     }

sql/core/src/main/scala/org/apache/spark/sql/execution/command/cache.scala

@@ -19,7 +19,6 @@ package org.apache.spark.sql.execution.command
 
 import org.apache.spark.sql.{Dataset, Row, SparkSession}
 import org.apache.spark.sql.catalyst.TableIdentifier
-import org.apache.spark.sql.catalyst.analysis.NoSuchTableException
 import org.apache.spark.sql.catalyst.plans.QueryPlan
 import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan
 

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSourceStrategy.scala

@@ -78,11 +78,11 @@ case class DataSourceAnalysis(conf: SQLConf) extends Rule[LogicalPlan] with Cast
           s"assigned constant values.")
     }
 
-    if (providedPartitions.size != targetPartitionSchema.fields.size) {
+    if (providedPartitions.size != targetPartitionSchema.fields.length) {
       throw new AnalysisException(
         s"The data to be inserted needs to have the same number of " +
           s"partition columns as the target table: target table " +
-          s"has ${targetPartitionSchema.fields.size} partition column(s) but the inserted " +
+          s"has ${targetPartitionSchema.fields.length} partition column(s) but the inserted " +
           s"data has ${providedPartitions.size} partition columns specified.")
     }
 
@@ -124,9 +124,9 @@ case class DataSourceAnalysis(conf: SQLConf) extends Rule[LogicalPlan] with Cast
 
     assert(partitionList.take(staticPartitions.size).forall(_.isDefined))
     val projectList =
-      sourceAttributes.take(targetAttributes.size - targetPartitionSchema.fields.size) ++
+      sourceAttributes.take(targetAttributes.size - targetPartitionSchema.fields.length) ++
         partitionList.take(staticPartitions.size).map(_.get) ++
-        sourceAttributes.takeRight(targetPartitionSchema.fields.size - staticPartitions.size)
+        sourceAttributes.takeRight(targetPartitionSchema.fields.length - staticPartitions.size)
 
     projectList
   }

sql/core/src/test/scala/org/apache/spark/sql/test/SQLTestUtils.scala

@@ -40,7 +40,6 @@ import org.apache.spark.sql.catalyst.plans.PlanTestBase
 import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan
 import org.apache.spark.sql.catalyst.util._
 import org.apache.spark.sql.execution.FilterExec
-import org.apache.spark.sql.internal.SQLConf
 import org.apache.spark.util.UninterruptibleThread
 import org.apache.spark.util.Utils
 

sql/hive/src/test/scala/org/apache/spark/sql/hive/CachedTableSuite.scala

@@ -20,7 +20,6 @@ package org.apache.spark.sql.hive
 import java.io.File
 
 import org.apache.spark.sql.{AnalysisException, Dataset, QueryTest, SaveMode}
-import org.apache.spark.sql.catalyst.analysis.NoSuchTableException
 import org.apache.spark.sql.catalyst.parser.ParseException
 import org.apache.spark.sql.execution.columnar.InMemoryTableScanExec
 import org.apache.spark.sql.execution.datasources.{CatalogFileIndex, HadoopFsRelation, LogicalRelation}

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

@@ -23,8 +23,6 @@ import org.apache.hadoop.hive.ql.udf.generic.GenericUDAFMax
 import org.scalatest.Matchers._
 
 import org.apache.spark.sql._
-import org.apache.spark.sql.catalyst.FunctionIdentifier
-import org.apache.spark.sql.catalyst.analysis.UnresolvedFunction
 import org.apache.spark.sql.catalyst.expressions.{ExpressionEvalHelper, Literal}
 import org.apache.spark.sql.catalyst.expressions.aggregate.ApproximatePercentile
 import org.apache.spark.sql.execution.aggregate.{HashAggregateExec, ObjectHashAggregateExec, SortAggregateExec}