[sql] Rename Expression.apply to eval for better readability.

Also used this opportunity to add a bunch of override's and made some members private.

Author: Reynold Xin <rxin@apache.org>

Closes #340 from rxin/eval and squashes the following commits:

a7c7ca7 [Reynold Xin] Fixed conflicts in merge.
9069de6 [Reynold Xin] Merge branch 'master' into eval
3ccc313 [Reynold Xin] Merge branch 'master' into eval
1a47e10 [Reynold Xin] Renamed apply to eval for generators and added a bunch of override's.
ea061de [Reynold Xin] Rename Expression.apply to eval for better readability.

2 files changed, 8 insertions, 8 deletions

diff --git a/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveOperators.scala b/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveOperators.scala
index e2d9d8de25..821fb22112 100644
--- a/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveOperators.scala
+++ b/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveOperators.scala
@@ -106,7 +106,7 @@ case class HiveTableScan(
   }
 
   private def castFromString(value: String, dataType: DataType) = {
-    Cast(Literal(value), dataType).apply(null)
+    Cast(Literal(value), dataType).eval(null)
   }
 
   @transient
@@ -134,7 +134,7 @@ case class HiveTableScan(
         // Only partitioned values are needed here, since the predicate has already been bound to
         // partition key attribute references.
         val row = new GenericRow(castedValues.toArray)
-        shouldKeep.apply(row).asInstanceOf[Boolean]
+        shouldKeep.eval(row).asInstanceOf[Boolean]
       }
     }
   }
diff --git a/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveUdfs.scala b/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveUdfs.scala
index 2c607455c8..f9b437d435 100644
--- a/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveUdfs.scala
+++ b/sql/hive/src/main/scala/org/apache/spark/sql/hive/hiveUdfs.scala
@@ -190,8 +190,8 @@ case class HiveSimpleUdf(name: String, children: Seq[Expression]) extends HiveUd
   }
 
   // TODO: Finish input output types.
-  override def apply(input: Row): Any = {
-    val evaluatedChildren = children.map(_.apply(input))
+  override def eval(input: Row): Any = {
+    val evaluatedChildren = children.map(_.eval(input))
     // Wrap the function arguments in the expected types.
     val args = evaluatedChildren.zip(wrappers).map {
       case (arg, wrapper) => wrapper(arg)
@@ -216,12 +216,12 @@ case class HiveGenericUdf(
 
   val dataType: DataType = inspectorToDataType(returnInspector)
 
-  override def apply(input: Row): Any = {
+  override def eval(input: Row): Any = {
     returnInspector // Make sure initialized.
     val args = children.map { v =>
       new DeferredObject {
         override def prepare(i: Int) = {}
-        override def get(): AnyRef = wrap(v.apply(input))
+        override def get(): AnyRef = wrap(v.eval(input))
       }
     }.toArray
     unwrap(function.evaluate(args))
@@ -406,7 +406,7 @@ case class HiveGenericUdtf(
     }
   }
 
-  override def apply(input: Row): TraversableOnce[Row] = {
+  override def eval(input: Row): TraversableOnce[Row] = {
     outputInspectors // Make sure initialized.
 
     val inputProjection = new Projection(children)
@@ -460,7 +460,7 @@ case class HiveUdafFunction(
   private val buffer =
     function.getNewAggregationBuffer.asInstanceOf[GenericUDAFEvaluator.AbstractAggregationBuffer]
 
-  override def apply(input: Row): Any = unwrapData(function.evaluate(buffer), returnInspector)
+  override def eval(input: Row): Any = unwrapData(function.evaluate(buffer), returnInspector)
 
   @transient
   val inputProjection = new Projection(exprs)