update: aggregate functions structure and evalute

Author: MiriamGaus

src/main/java/de/vill/model/expression/AggregateFunctionExpression.java

@@ -2,7 +2,6 @@
 
 import static de.vill.util.Util.addNecessaryQuotes;
 
-import de.vill.model.Attribute;
 import de.vill.model.Feature;
 import de.vill.model.GlobalAttribute;
 import de.vill.model.building.VariableReference;
@@ -12,7 +11,7 @@
 import java.util.Objects;
 import java.util.Set;
 
-public class AggregateFunctionExpression extends Expression {
+public abstract class AggregateFunctionExpression extends Expression {
 
     protected GlobalAttribute attribute;
     protected Feature rootFeature;
@@ -58,10 +57,7 @@ public GlobalAttribute getAttribute() {
 
 
     @Override
-    public double evaluate(Set<Feature> selectedFeatures) {
-        // TODO not necessary for now
-        return 0;
-    }
+    abstract public double evaluate(Set<Feature> selectedFeatures);
 
     protected String toString(boolean withSubmodels, String functionName, String currentAlias) {
         final StringBuilder result = new StringBuilder();

src/main/java/de/vill/model/expression/AvgAggregateFunctionExpression.java

@@ -3,12 +3,32 @@
 import de.vill.model.Attribute;
 import de.vill.model.Feature;
 import de.vill.model.GlobalAttribute;
-import de.vill.model.building.VariableReference;
 import de.vill.util.Constants;
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 
 public class AvgAggregateFunctionExpression extends AggregateFunctionExpression {
+    /**
+     * Evaluates the average of the values of the selected features.
+     *
+     * @param selectedFeatures The set of selected features.
+     * @return The average of the values of the selected features.
+     */
+    @Override
+    public double evaluate(Set<Feature> selectedFeatures) {
+        double sum = 0;
+        double count = 0;
+        for (Feature feature : selectedFeatures) {
+            Attribute<?> attribute = feature.getAttributes().get(getAttribute().getIdentifier());
+            if (attribute != null && attribute.getValue() instanceof Number) {
+                sum += ((Number) attribute.getValue()).doubleValue();
+                count++;
+            }
+        }
+        return count == 0 ? 0 : sum / count;
+    }
+    
     public AvgAggregateFunctionExpression(GlobalAttribute reference) {
         super(reference);
     }

src/main/java/de/vill/model/expression/LengthAggregateFunctionExpression.java

@@ -1,7 +1,5 @@
 package de.vill.model.expression;
 
-import com.google.errorprone.annotations.Var;
-import de.vill.model.Attribute;
 import de.vill.model.Feature;
 import de.vill.model.building.VariableReference;
 import de.vill.util.Constants;

src/main/java/de/vill/model/expression/MaxAggregateFunctionExpression.java

@@ -3,12 +3,31 @@
 import de.vill.model.Attribute;
 import de.vill.model.Feature;
 import de.vill.model.GlobalAttribute;
-import de.vill.model.building.VariableReference;
+
 
 import java.util.Arrays;
 import java.util.List;
+import java.util.Set;
 
 public class MaxAggregateFunctionExpression extends AggregateFunctionExpression {
+    /**
+     * Evaluates the maximum of the values of the selected features.
+     *
+     * @param selectedFeatures The set of selected features.
+     * @return The maximum of the values of the selected features.
+     */
+    @Override
+    public double evaluate(Set<Feature> selectedFeatures) {
+        double max = Double.NEGATIVE_INFINITY;
+        for (Feature feature : selectedFeatures) {
+            Attribute<?> attribute = feature.getAttributes().get(getAttribute().getIdentifier());
+            if (attribute != null && attribute.getValue() instanceof Number) {
+                max = Math.max(max, ((Number) attribute.getValue()).doubleValue());
+            }
+        }
+        return max == Double.NEGATIVE_INFINITY ? 0 : max;
+    }
+    
     public MaxAggregateFunctionExpression(GlobalAttribute attribute) {
         super(attribute);
     }

src/main/java/de/vill/model/expression/MinAggregateFunctionExpression.java

@@ -3,14 +3,32 @@
 import de.vill.model.Attribute;
 import de.vill.model.Feature;
 import de.vill.model.GlobalAttribute;
-import de.vill.model.building.VariableReference;
-import org.w3c.dom.Attr;
+
 
 import java.util.Arrays;
 import java.util.List;
+import java.util.Set;
 
 public class MinAggregateFunctionExpression extends AggregateFunctionExpression {
 
+    /**
+     * Evaluates the minimum of the values of the selected features.
+     *
+     * @param selectedFeatures The set of selected features.
+     * @return The minimum of the values of the selected features.
+     */
+    @Override
+    public double evaluate(Set<Feature> selectedFeatures) {
+        double min = Double.POSITIVE_INFINITY;
+        for (Feature feature : selectedFeatures) {
+            Attribute<?> attribute = feature.getAttributes().get(getAttribute().getIdentifier());
+            if (attribute != null && attribute.getValue() instanceof Number) {
+                min = Math.min(min, ((Number) attribute.getValue()).doubleValue());
+            }
+        }
+        return min == Double.POSITIVE_INFINITY ? 0 : min;
+    }
+
     public MinAggregateFunctionExpression(GlobalAttribute attribute) {
         super(attribute);
     }

src/main/java/de/vill/model/expression/SumAggregateFunctionExpression.java

@@ -6,8 +6,27 @@
 import de.vill.util.Constants;
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 
 public class SumAggregateFunctionExpression extends AggregateFunctionExpression {
+
+    /**
+     * Evaluates the sum of the values of the selected features.
+     *
+     * @param selectedFeatures The set of selected features.
+     * @return The sum of the values of the selected features.
+     */
+    @Override
+    public double evaluate(Set<Feature> selectedFeatures) {
+        double sum = 0;
+        for (Feature feature : selectedFeatures) {
+            Attribute<?> attribute = feature.getAttributes().get(getAttribute().getIdentifier());
+            if (attribute != null && attribute.getValue() instanceof Number) {
+                sum += ((Number) attribute.getValue()).doubleValue();
+            }
+        }
+        return sum;
+    }
     public SumAggregateFunctionExpression(GlobalAttribute attribute) {
         super(attribute);
     }