Fixes #9 (#30)

* feat: implemented injectable factory method for UVLListener and UVLModelFactory

* fix: Use DefaultUVLElementFactory in constructor instead of null

* fix: removed null check in createUVLListener

---------

Co-authored-by: Julia Pham <j.pham@tu-braunschweig.de>

Author: JuliaCoolia

src/main/java/de/vill/main/UVLListener.java

@@ -49,7 +49,15 @@
 import org.antlr.v4.runtime.Token;
 
 public class UVLListener extends UVLJavaParserBaseListener {
-    public FeatureModelBuilder fmBuilder = new FeatureModelBuilder();
+    public FeatureModelBuilder fmBuilder;
+
+    public UVLListener() {
+        this(new FeatureModelBuilder());
+    }
+
+    public UVLListener(FeatureModelBuilder fmBuilder) {
+        this.fmBuilder = fmBuilder;
+    }
     private Set<LanguageLevel> importedLanguageLevels = new HashSet<>(Arrays.asList(LanguageLevel.BOOLEAN_LEVEL));
     private Stack<Feature> featureStack = new Stack<>();
     private Stack<Group> groupStack = new Stack<>();

src/main/java/de/vill/main/UVLModelFactory.java

@@ -1,6 +1,9 @@
 package de.vill.main;
 
 import de.vill.model.*;
+import de.vill.model.building.AbstractUVLElementFactory;
+import de.vill.model.building.DefaultUVLElementFactory;
+import de.vill.model.building.FeatureModelBuilder;
 import de.vill.model.building.VariableReference;
 import de.vill.model.constraint.*;
 import de.vill.model.expression.*;
@@ -43,10 +46,16 @@ public class UVLModelFactory {
 
     private final Map<LanguageLevel, Class<? extends IConversionStrategy>> conversionStrategiesDrop;
     private final Map<LanguageLevel, Class<? extends IConversionStrategy>> conversionStrategiesConvert;
+    private final AbstractUVLElementFactory elementFactory;
 
     private final List<ParseError> errorList = new LinkedList<>();
 
     public UVLModelFactory() {
+        this(new DefaultUVLElementFactory());
+    }
+
+    public UVLModelFactory(AbstractUVLElementFactory elementFactory) {
+        this.elementFactory = elementFactory;
         this.conversionStrategiesDrop = new HashMap<>();
         this.conversionStrategiesDrop.put(LanguageLevel.GROUP_CARDINALITY, DropGroupCardinality.class);
         this.conversionStrategiesDrop.put(LanguageLevel.FEATURE_CARDINALITY, DropFeatureCardinality.class);
@@ -124,7 +133,7 @@ public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int
             }
         });
 
-        UVLListener uvlListener = new UVLListener();
+        UVLListener uvlListener = createUVLListener();
         ParseTreeWalker walker = new ParseTreeWalker();
         walker.walk(uvlListener, UVLJavaParser.constraintLine());
 
@@ -272,6 +281,10 @@ private List<LanguageLevel> getActualLanguageLevelsToRemoveInOrder(FeatureModel
         return completeOrderedLevelsToRemove;
     }
 
+    private UVLListener createUVLListener() {
+        return new UVLListener(new FeatureModelBuilder(elementFactory));
+    }
+
     private String getPath(String rootPath, Import referencedImport) {
         return rootPath + FileSystems.getDefault().getSeparator() + referencedImport.getNamespace().replace(".", FileSystems.getDefault().getSeparator()) + ".uvl";
     }
@@ -301,7 +314,7 @@ public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int
         });
 
 
-        UVLListener uvlListener = new UVLListener();
+        UVLListener uvlListener = createUVLListener();
         ParseTreeWalker walker = new ParseTreeWalker();
         walker.walk(uvlListener, UVLJavaParser.featureModel());
         FeatureModel featureModel = null;