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Author: przemekwitek

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/dataframe/analyses/BoostedTreeParams.java

@@ -76,6 +76,10 @@ static void declareFields(AbstractObjectParser<?, Void> parser) {
         this.featureBagFraction = featureBagFraction;
     }
 
+    BoostedTreeParams() {
+        this(null, null, null, null, null);
+    }
+
     BoostedTreeParams(StreamInput in) throws IOException {
         lambda = in.readOptionalDouble();
         gamma = in.readOptionalDouble();

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/dataframe/analyses/Classification.java

@@ -61,7 +61,7 @@ public static Classification fromXContent(XContentParser parser, boolean ignoreU
     private final String dependentVariable;
     private final BoostedTreeParams boostedTreeParams;
     private final String predictionFieldName;
-    private final Integer numTopClasses;
+    private final int numTopClasses;
     private final double trainingPercent;
 
     public Classification(String dependentVariable,
@@ -78,12 +78,12 @@ public Classification(String dependentVariable,
         this.dependentVariable = ExceptionsHelper.requireNonNull(dependentVariable, DEPENDENT_VARIABLE);
         this.boostedTreeParams = ExceptionsHelper.requireNonNull(boostedTreeParams, BoostedTreeParams.NAME);
         this.predictionFieldName = predictionFieldName;
-        this.numTopClasses = numTopClasses;
+        this.numTopClasses = numTopClasses == null ? 0 : numTopClasses;
         this.trainingPercent = trainingPercent == null ? 100.0 : trainingPercent;
     }
 
     public Classification(String dependentVariable) {
-        this(dependentVariable, new BoostedTreeParams(null, null, null, null, null), null, null, null);
+        this(dependentVariable, new BoostedTreeParams(), null, null, null);
     }
 
     public Classification(StreamInput in) throws IOException {
@@ -121,9 +121,7 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         builder.startObject();
         builder.field(DEPENDENT_VARIABLE.getPreferredName(), dependentVariable);
         boostedTreeParams.toXContent(builder, params);
-        if (numTopClasses != null) {
-            builder.field(NUM_TOP_CLASSES.getPreferredName(), numTopClasses);
-        }
+        builder.field(NUM_TOP_CLASSES.getPreferredName(), numTopClasses);
         if (predictionFieldName != null) {
             builder.field(PREDICTION_FIELD_NAME.getPreferredName(), predictionFieldName);
         }
@@ -137,9 +135,7 @@ public Map<String, Object> getParams() {
         Map<String, Object> params = new HashMap<>();
         params.put(DEPENDENT_VARIABLE.getPreferredName(), dependentVariable);
         params.putAll(boostedTreeParams.getParams());
-        if (numTopClasses != null) {
-            params.put(NUM_TOP_CLASSES.getPreferredName(), numTopClasses);
-        }
+        params.put(NUM_TOP_CLASSES.getPreferredName(), numTopClasses);
         if (predictionFieldName != null) {
             params.put(PREDICTION_FIELD_NAME.getPreferredName(), predictionFieldName);
         }

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/dataframe/analyses/Regression.java

@@ -74,7 +74,7 @@ public Regression(String dependentVariable,
     }
 
     public Regression(String dependentVariable) {
-        this(dependentVariable, new BoostedTreeParams(null, null, null, null, null), null, null);
+        this(dependentVariable, new BoostedTreeParams(), null, null);
     }
 
     public Regression(StreamInput in) throws IOException {

x-pack/plugin/src/test/resources/rest-api-spec/test/ml/data_frame_analytics_crud.yml

@@ -1564,7 +1564,8 @@ setup:
       "eta": 0.5,
       "maximum_number_trees": 400,
       "feature_bag_fraction": 0.3,
-      "training_percent": 60.3
+      "training_percent": 60.3,
+      "num_top_classes": 0
     }
   }}
   - is_true: create_time