remove final; rename cardinality to numValues

Author: mengxr

mllib/src/main/scala/org/apache/spark/ml/attribute/AttributeKeys.scala

@@ -21,17 +21,17 @@ package org.apache.spark.ml.attribute
  * Keys used to store attributes.
  */
 private[attribute] object AttributeKeys {
-  final val ML_ATTR: String = "ml_attr"
-  final val TYPE: String = "type"
-  final val NAME: String = "name"
-  final val INDEX: String = "idx"
-  final val VALUES: String = "vals"
-  final val MIN: String = "min"
-  final val MAX: String = "max"
-  final val STD: String = "std"
-  final val SPARSITY: String = "sparsity"
-  final val ORDINAL: String = "ord"
-  final val CARDINALITY: String = "card"
-  final val ATTRIBUTES: String = "attrs"
-  final val NUM_ATTRIBUTES: String = "num_attrs"
+  val ML_ATTR: String = "ml_attr"
+  val TYPE: String = "type"
+  val NAME: String = "name"
+  val INDEX: String = "idx"
+  val MIN: String = "min"
+  val MAX: String = "max"
+  val STD: String = "std"
+  val SPARSITY: String = "sparsity"
+  val ORDINAL: String = "ord"
+  val VALUES: String = "vals"
+  val NUM_VALUES: String = "num_vals"
+  val ATTRIBUTES: String = "attrs"
+  val NUM_ATTRIBUTES: String = "num_attrs"
 }

mllib/src/main/scala/org/apache/spark/ml/attribute/AttributeType.scala

@@ -26,19 +26,19 @@ sealed abstract class AttributeType(val name: String)
 object AttributeType {
 
   /** Numeric type. */
-  final val Numeric: AttributeType = {
+  val Numeric: AttributeType = {
     case object Numeric extends AttributeType("numeric")
     Numeric
   }
 
   /** Nominal type. */
-  final val Nominal: AttributeType = {
+  val Nominal: AttributeType = {
     case object Nominal extends AttributeType("nominal")
     Nominal
   }
 
   /** Binary type. */
-  final val Binary: AttributeType = {
+  val Binary: AttributeType = {
     case object Binary extends AttributeType("binary")
     Binary
   }

mllib/src/main/scala/org/apache/spark/ml/attribute/attributes.scala

@@ -370,7 +370,7 @@ class NominalAttribute private[ml] (
     name.foreach(bldr.putString(NAME, _))
     index.foreach(bldr.putLong(INDEX, _))
     isOrdinal.foreach(bldr.putBoolean(ORDINAL, _))
-    numValues.foreach(bldr.putLong(CARDINALITY, _))
+    numValues.foreach(bldr.putLong(NUM_VALUES, _))
     values.foreach(v => bldr.putStringArray(VALUES, v))
     bldr.build()
   }
@@ -410,11 +410,11 @@ object NominalAttribute extends AttributeFactory {
     val name = if (metadata.contains(NAME)) Some(metadata.getString(NAME)) else None
     val index = if (metadata.contains(INDEX)) Some(metadata.getLong(INDEX).toInt) else None
     val isOrdinal = if (metadata.contains(ORDINAL)) Some(metadata.getBoolean(ORDINAL)) else None
-    val cardinality =
-      if (metadata.contains(CARDINALITY)) Some(metadata.getLong(CARDINALITY).toInt) else None
+    val numValues =
+      if (metadata.contains(NUM_VALUES)) Some(metadata.getLong(NUM_VALUES).toInt) else None
     val values =
       if (metadata.contains(VALUES)) Some(metadata.getStringArray(VALUES)) else None
-    new NominalAttribute(name, index, isOrdinal, cardinality, values)
+    new NominalAttribute(name, index, isOrdinal, numValues, values)
   }
 }