parent ref for ASTNode.java

lang/src/main/java/edu/kit/iti/formal/psdbg/parser/ast/ASTNode.java

@@ -26,8 +26,11 @@ package edu.kit.iti.formal.psdbg.parser.ast;
 import edu.kit.iti.formal.psdbg.parser.Visitable;
 import edu.kit.iti.formal.psdbg.parser.Visitor;
 import lombok.Getter;
+import lombok.Setter;
 import org.antlr.v4.runtime.ParserRuleContext;
 
+import javax.annotation.Nullable;
+
 /**
  * @author Alexander Weigl
  * @version 1 (27.04.17)
@@ -39,6 +42,12 @@ public abstract class ASTNode<T extends ParserRuleContext>
      */
     protected T ruleContext;
 
+    /**
+     *
+     */
+    @Getter @Setter @Nullable
+    protected ASTNode parent;
+
     /**
      *
      */
@@ -56,6 +65,7 @@ public abstract class ASTNode<T extends ParserRuleContext>
      *
      * @return
      */
+    @Nullable
     public String getOrigin() {
         if (ruleContext != null) {
             String src = ruleContext.getStart().getInputStream().getSourceName();