feat: added abstract factory and default factory

Author: Julia Pham

src/main/java/de/vill/model/building/AbstractUVLElementFactory.java

@@ -0,0 +1,14 @@
+package de.vill.model.building;
+
+import de.vill.exception.ParseError;
+import de.vill.model.*;
+
+public abstract class AbstractUVLElementFactory {
+    
+    public abstract Feature createFeature(String name);
+
+    public abstract <T> Attribute<T> createAttribute(String name, T value, Feature correspondingFeature);
+
+    public abstract GlobalAttribute createGlobalAttribute(String identifier, FeatureModel featureModel);
+
+}

src/main/java/de/vill/model/building/DefaultUVLElementFactory.java

@@ -0,0 +1,22 @@
+package de.vill.model.building;
+
+import de.vill.exception.ParseError;
+import de.vill.model.*;
+
+public class DefaultUVLElementFactory extends AbstractUVLElementFactory{
+
+    @Override
+    public Feature createFeature(String name){
+        return new Feature(name);
+    }
+
+    @Override
+    public <T> Attribute<T> createAttribute(String name, T value, Feature correspondingFeature){
+        return new Attribute<>(name, value, correspondingFeature);
+    }   
+
+    @Override
+    public GlobalAttribute createGlobalAttribute(String identifier, FeatureModel featureModel){
+        return new GlobalAttribute(identifier, featureModel);
+    }
+}

src/main/java/de/vill/model/building/FeatureModelBuilder.java

@@ -11,14 +11,20 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Function;
 
 /**
  *
  */
 public class FeatureModelBuilder {
 
+    private Function<String, Feature> featureFactory = Feature::new;
     private FeatureModel fmInConstruction;
 
+    public void setFeatureFactory(Function<String, Feature> featureFactory){
+        this.featureFactory = featureFactory;
+    } 
+
     public FeatureModelBuilder() {
         fmInConstruction = new FeatureModel();
     }
@@ -27,7 +33,6 @@ public FeatureModelBuilder(FeatureModel old) {
         fmInConstruction = old;
     }
 
-
     public void addImport(Import importToAdd) {
         fmInConstruction.getImports().add(importToAdd);
     }
@@ -49,7 +54,7 @@ public boolean setRootFeature(Feature feature) {
     }
 
     public Feature addRootFeature(String featureName, FeatureType featureType, Cardinality cardinality) {
-        Feature rootFeature = new Feature(featureName);
+        Feature rootFeature = featureFactory.apply(featureName);
         rootFeature.setFeatureType(featureType);
         rootFeature.setCardinality(cardinality);
 
@@ -71,7 +76,7 @@ public Feature addFeature(String featureName, Group group, Import featureOrigin,
     }
 
     public Feature addFeature(String featureName, Group group, Import featureOrigin, FeatureType type, Cardinality cardinality) {
-        Feature feature = new Feature(featureName);
+        Feature feature = featureFactory.apply(featureName);
         feature.setRelatedImport(featureOrigin);
         feature.setFeatureType(type);
         feature.setCardinality(cardinality);