Add methods to navigate to the root node of an AST

2 files changed, 27 insertions, 4 deletions

diff --git a/javaparser-core/src/main/java/com/github/javaparser/ast/Node.java b/javaparser-core/src/main/java/com/github/javaparser/ast/Node.java
index 0d7c822c8..5f45e75b0 100644
--- a/javaparser-core/src/main/java/com/github/javaparser/ast/Node.java
+++ b/javaparser-core/src/main/java/com/github/javaparser/ast/Node.java
@@ -41,11 +41,12 @@ import com.github.javaparser.metamodel.NodeMetaModel;
 import com.github.javaparser.metamodel.PropertyMetaModel;
 import com.github.javaparser.printer.PrettyPrinter;
 import com.github.javaparser.printer.PrettyPrinterConfiguration;
+
 import javax.annotation.Generated;
 import java.util.*;
+
 import static com.github.javaparser.ast.Node.Parsedness.PARSED;
 import static java.util.Collections.unmodifiableList;
-import com.github.javaparser.ast.Node;
 
 /**
  * Base class for all nodes of the abstract syntax tree.
@@ -297,8 +298,7 @@ public abstract class Node implements Cloneable, HasParentNode<Node>, Visitable,
 
     /**
      * Contains all nodes that have this node set as their parent.
-     * You can add nodes to it by setting a node's parent to this node.
-     * You can remove nodes from it by setting a child node's parent to something other than this node.
+     * You can add and remove nodes from this list by adding or removing nodes from the fields of this node.
      *
      * @return all nodes that have this node as their parent.
      */
@@ -641,4 +641,26 @@ public abstract class Node implements Cloneable, HasParentNode<Node>, Visitable,
         }
         return false;
     }
+
+    /**
+     * Finds the root node of this AST by finding the topmost parent.
+     */
+    public Node findRootNode() {
+        Node n = this;
+        while (n.getParentNode().isPresent()) {
+            n = n.getParentNode().get();
+        }
+        return n;
+    }
+
+    /**
+     * @return the containing CompilationUnit, or empty if this node is not inside a compilation unit.
+     */
+    public Optional<CompilationUnit> findCompilationUnit() {
+        Node rootNode = findRootNode();
+        if (rootNode instanceof CompilationUnit) {
+            return Optional.of((CompilationUnit) rootNode);
+        }
+        return Optional.empty();
+    }
 }
diff --git a/javaparser-core/src/main/java/com/github/javaparser/ast/body/VariableDeclarator.java b/javaparser-core/src/main/java/com/github/javaparser/ast/body/VariableDeclarator.java
index 79b906ad8..9de15f596 100644
--- a/javaparser-core/src/main/java/com/github/javaparser/ast/body/VariableDeclarator.java
+++ b/javaparser-core/src/main/java/com/github/javaparser/ast/body/VariableDeclarator.java
@@ -30,6 +30,7 @@ import com.github.javaparser.ast.nodeTypes.NodeWithType;
 import com.github.javaparser.ast.nodeTypes.NodeWithVariables;
 import com.github.javaparser.ast.observer.AstObserverAdapter;
 import com.github.javaparser.ast.observer.ObservableProperty;
+import com.github.javaparser.ast.type.ClassOrInterfaceType;
 import com.github.javaparser.ast.type.Type;
 import com.github.javaparser.ast.visitor.CloneVisitor;
 import com.github.javaparser.ast.visitor.GenericVisitor;
@@ -61,7 +62,7 @@ public final class VariableDeclarator extends Node implements NodeWithType<Varia
     private Type type;
 
     public VariableDeclarator() {
-        this(null, new SimpleName(), null);
+        this(null, new ClassOrInterfaceType(), new SimpleName(), null);
     }
 
     public VariableDeclarator(Type type, String variableName) {