fix: replace hard-coded constructors with factory in FMBuilder

Author: Julia Pham

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

@@ -2,6 +2,7 @@
 
 import de.vill.exception.ParseError;
 import de.vill.model.*;
+import de.vill.model.constraint.LiteralConstraint;
 
 public abstract class AbstractUVLElementFactory {
 
@@ -11,4 +12,6 @@ public abstract class AbstractUVLElementFactory {
 
     public abstract GlobalAttribute createGlobalAttribute(String identifier, FeatureModel featureModel);
 
+   // public abstract LiteralConstraint createFeatureLiteral(String name);
+
 }

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

@@ -2,6 +2,7 @@
 
 import de.vill.exception.ParseError;
 import de.vill.model.*;
+import de.vill.model.constraint.LiteralConstraint;
 
 public class DefaultUVLElementFactory extends AbstractUVLElementFactory{
 
@@ -19,4 +20,9 @@ public <T> Attribute<T> createAttribute(String name, T value, Feature correspond
     public GlobalAttribute createGlobalAttribute(String identifier, FeatureModel featureModel){
         return new GlobalAttribute(identifier, featureModel);
     }
+
+    // @Override
+    // public LiteralConstraint createFeatureLiteral(String name){
+    //     return new LiteralConstraint(fmInConstruction.getFeatureMap().get(name));
+    // }
 }

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

@@ -19,14 +19,22 @@
 public class FeatureModelBuilder {
 
     private Function<String, Feature> featureFactory = Feature::new;
+    
     private FeatureModel fmInConstruction;
 
+    private AbstractUVLElementFactory elementFactory;
+
     public void setFeatureFactory(Function<String, Feature> featureFactory){
         this.featureFactory = featureFactory;
     } 
 
     public FeatureModelBuilder() {
-        fmInConstruction = new FeatureModel();
+        this(new DefaultUVLElementFactory());
+    }
+
+    public FeatureModelBuilder(AbstractUVLElementFactory factory) {
+        this.elementFactory = factory;
+        this.fmInConstruction = new FeatureModel();
     }
 
     public FeatureModelBuilder(FeatureModel old) {
@@ -197,7 +205,7 @@ public LiteralConstraint createFeatureLiteral(String name) {
     }
 
     public GlobalAttribute createGlobalAttribute(String name) {
-        GlobalAttribute toCreate = new GlobalAttribute(name, fmInConstruction);
+        GlobalAttribute toCreate = elementFactory.createGlobalAttribute(name, fmInConstruction);
         if (toCreate.getType() == null) {
             System.err.println("Tried to reference " + name + " but attribute with that name does not exist");
             return null;