1 files changed, 8 insertions, 5 deletions
diff --git a/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala b/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala
index 461905c127..4249ff5c1e 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala
@@ -24,7 +24,7 @@ import org.apache.spark.annotation.AlphaComponent
 import org.apache.spark.ml.{PredictionModel, Predictor}
 import org.apache.spark.ml.param.{Param, ParamMap}
 import org.apache.spark.ml.tree.{GBTParams, TreeRegressorParams, DecisionTreeModel, TreeEnsembleModel}
-import org.apache.spark.ml.util.MetadataUtils
+import org.apache.spark.ml.util.{Identifiable, MetadataUtils}
 import org.apache.spark.mllib.linalg.Vector
 import org.apache.spark.mllib.regression.LabeledPoint
 import org.apache.spark.mllib.tree.{GradientBoostedTrees => OldGBT}
@@ -42,10 +42,12 @@ import org.apache.spark.sql.DataFrame
  * It supports both continuous and categorical features.
  */
 @AlphaComponent
-final class GBTRegressor
+final class GBTRegressor(override val uid: String)
   extends Predictor[Vector, GBTRegressor, GBTRegressionModel]
   with GBTParams with TreeRegressorParams with Logging {
 
+  def this() = this(Identifiable.randomUID("gbtr"))
+
   // Override parameter setters from parent trait for Java API compatibility.
 
   // Parameters from TreeRegressorParams:
@@ -149,7 +151,7 @@ object GBTRegressor {
  */
 @AlphaComponent
 final class GBTRegressionModel(
-    override val parent: GBTRegressor,
+    override val uid: String,
     private val _trees: Array[DecisionTreeRegressionModel],
     private val _treeWeights: Array[Double])
   extends PredictionModel[Vector, GBTRegressionModel]
@@ -173,7 +175,7 @@ final class GBTRegressionModel(
   }
 
   override def copy(extra: ParamMap): GBTRegressionModel = {
-    copyValues(new GBTRegressionModel(parent, _trees, _treeWeights), extra)
+    copyValues(new GBTRegressionModel(uid, _trees, _treeWeights), extra)
   }
 
   override def toString: String = {
@@ -199,6 +201,7 @@ private[ml] object GBTRegressionModel {
       // parent, fittingParamMap for each tree is null since there are no good ways to set these.
       DecisionTreeRegressionModel.fromOld(tree, null, categoricalFeatures)
     }
-    new GBTRegressionModel(parent, newTrees, oldModel.treeWeights)
+    val uid = if (parent != null) parent.uid else Identifiable.randomUID("gbtr")
+    new GBTRegressionModel(parent.uid, newTrees, oldModel.treeWeights)
   }
 }