diff --git a/js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitor.kt b/js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitor.kt
index 6d66d655981..93c2eebf47f 100644
--- a/js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitor.kt
+++ b/js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitor.kt
@@ -2,209 +2,163 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-package com.google.dart.compiler.backend.js.ast;
+package com.google.dart.compiler.backend.js.ast
 
-import com.google.dart.compiler.backend.js.ast.JsVars.JsVar;
-
-import java.util.List;
+import com.google.dart.compiler.backend.js.ast.JsVars.JsVar
 
 public abstract class JsVisitor {
-    public <T extends JsNode> void accept(T node) {
-        node.accept(this);
+    public open fun <T : JsNode> accept(node: T) {
+        node.accept(this)
     }
 
-    public final <T extends JsNode> void acceptList(List<T> collection) {
-        for (T node : collection) {
-            accept(node);
+    public fun <T : JsNode> acceptList(collection: List<T>) {
+        for (node in collection) {
+            accept(node)
         }
     }
 
-    public void acceptLvalue(JsExpression expression) {
-        accept(expression);
+    public fun acceptLvalue(expression: JsExpression) {
+        accept(expression)
     }
 
-    public final <T extends JsNode> void acceptWithInsertRemove(List<T> collection) {
-        for (T node : collection) {
-            accept(node);
+    public fun <T : JsNode> acceptWithInsertRemove(collection: List<T>) {
+        for (node in collection) {
+            accept(node)
         }
     }
 
-    public void visitArrayAccess(JsArrayAccess x) {
-        visitElement(x);
-    }
+    public open fun visitArrayAccess(x: JsArrayAccess): Unit =
+            visitElement(x)
 
-    public void visitArray(JsArrayLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitArray(x: JsArrayLiteral): Unit =
+            visitElement(x)
 
-    public void visitBinaryExpression(JsBinaryOperation x) {
-        visitElement(x);
-    }
+    public open fun visitBinaryExpression(x: JsBinaryOperation): Unit =
+            visitElement(x)
 
-    public void visitBlock(JsBlock x) {
-        visitElement(x);
-    }
+    public open fun visitBlock(x: JsBlock): Unit =
+            visitElement(x)
 
-    public void visitBoolean(JsLiteral.JsBooleanLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitBoolean(x: JsLiteral.JsBooleanLiteral): Unit =
+            visitElement(x)
 
-    public void visitBreak(JsBreak x) {
-        visitElement(x);
-    }
+    public open fun visitBreak(x: JsBreak): Unit =
+            visitElement(x)
 
-    public void visitCase(JsCase x) {
-        visitElement(x);
-    }
+    public open fun visitCase(x: JsCase): Unit =
+            visitElement(x)
 
-    public void visitCatch(JsCatch x) {
-        visitElement(x);
-    }
+    public open fun visitCatch(x: JsCatch): Unit =
+            visitElement(x)
 
-    public void visitConditional(JsConditional x) {
-        visitElement(x);
-    }
+    public open fun visitConditional(x: JsConditional): Unit =
+            visitElement(x)
 
-    public void visitContinue(JsContinue x) {
-        visitElement(x);
-    }
+    public open fun visitContinue(x: JsContinue): Unit =
+            visitElement(x)
 
-    public void visitDebugger(JsDebugger x) {
-        visitElement(x);
-    }
+    public open fun visitDebugger(x: JsDebugger): Unit =
+            visitElement(x)
 
-    public void visitDefault(JsDefault x) {
-        visitElement(x);
-    }
+    public open fun visitDefault(x: JsDefault): Unit =
+            visitElement(x)
 
-    public void visitDoWhile(JsDoWhile x) {
-        visitElement(x);
-    }
+    public open fun visitDoWhile(x: JsDoWhile): Unit =
+            visitElement(x)
 
-    public void visitEmpty(JsEmpty x) {
-        visitElement(x);
-    }
+    public open fun visitEmpty(x: JsEmpty): Unit =
+            visitElement(x)
 
-    public void visitExpressionStatement(JsExpressionStatement x) {
-        visitElement(x);
-    }
+    public open fun visitExpressionStatement(x: JsExpressionStatement): Unit =
+            visitElement(x)
 
-    public void visitFor(JsFor x) {
-        visitElement(x);
-    }
+    public open fun visitFor(x: JsFor): Unit =
+            visitElement(x)
 
-    public void visitForIn(JsForIn x) {
-        visitElement(x);
-    }
+    public open fun visitForIn(x: JsForIn): Unit =
+            visitElement(x)
 
-    public void visitFunction(JsFunction x) {
-        visitElement(x);
-    }
+    public open fun visitFunction(x: JsFunction): Unit =
+            visitElement(x)
 
-    public void visitIf(JsIf x) {
-        visitElement(x);
-    }
+    public open fun visitIf(x: JsIf): Unit =
+            visitElement(x)
 
-    public void visitInvocation(JsInvocation invocation) {
-        visitElement(invocation);
-    }
+    public open fun visitInvocation(invocation: JsInvocation): Unit =
+            visitElement(invocation)
 
-    public void visitLabel(JsLabel x) {
-        visitElement(x);
-    }
+    public open fun visitLabel(x: JsLabel): Unit =
+            visitElement(x)
 
-    public void visitNameRef(JsNameRef nameRef) {
-        visitElement(nameRef);
-    }
+    public open fun visitNameRef(nameRef: JsNameRef): Unit =
+            visitElement(nameRef)
 
-    public void visitNew(JsNew x) {
-        visitElement(x);
-    }
+    public open fun visitNew(x: JsNew): Unit =
+            visitElement(x)
 
-    public void visitNull(JsNullLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitNull(x: JsNullLiteral): Unit =
+            visitElement(x)
 
-    public void visitInt(JsNumberLiteral.JsIntLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitInt(x: JsNumberLiteral.JsIntLiteral): Unit =
+            visitElement(x)
 
-    public void visitDouble(JsNumberLiteral.JsDoubleLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitDouble(x: JsNumberLiteral.JsDoubleLiteral): Unit =
+            visitElement(x)
 
-    public void visitObjectLiteral(JsObjectLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitObjectLiteral(x: JsObjectLiteral): Unit =
+            visitElement(x)
 
-    public void visitParameter(JsParameter x) {
-        visitElement(x);
-    }
+    public open fun visitParameter(x: JsParameter): Unit =
+            visitElement(x)
 
-    public void visitPostfixOperation(JsPostfixOperation x) {
-        visitElement(x);
-    }
+    public open fun visitPostfixOperation(x: JsPostfixOperation): Unit =
+            visitElement(x)
 
-    public void visitPrefixOperation(JsPrefixOperation x) {
-        visitElement(x);
-    }
+    public open fun visitPrefixOperation(x: JsPrefixOperation): Unit =
+            visitElement(x)
 
-    public void visitProgram(JsProgram x) {
-        visitElement(x);
-    }
+    public open fun visitProgram(x: JsProgram): Unit =
+            visitElement(x)
 
-    public void visitProgramFragment(JsProgramFragment x) {
-        visitElement(x);
-    }
+    public open fun visitProgramFragment(x: JsProgramFragment): Unit =
+            visitElement(x)
 
-    public void visitPropertyInitializer(JsPropertyInitializer x) {
-        visitElement(x);
-    }
+    public open fun visitPropertyInitializer(x: JsPropertyInitializer): Unit =
+            visitElement(x)
 
-    public void visitRegExp(JsRegExp x) {
-        visitElement(x);
-    }
+    public open fun visitRegExp(x: JsRegExp): Unit =
+            visitElement(x)
 
-    public void visitReturn(JsReturn x) {
-        visitElement(x);
-    }
+    public open fun visitReturn(x: JsReturn): Unit =
+            visitElement(x)
 
-    public void visitString(JsStringLiteral x) {
-        visitElement(x);
-    }
+    public open fun visitString(x: JsStringLiteral): Unit =
+            visitElement(x)
 
-    public void visit(JsSwitch x) {
-        visitElement(x);
-    }
+    public open fun visit(x: JsSwitch): Unit =
+            visitElement(x)
 
-    public void visitThis(JsLiteral.JsThisRef x) {
-        visitElement(x);
-    }
+    public open fun visitThis(x: JsLiteral.JsThisRef): Unit =
+            visitElement(x)
 
-    public void visitThrow(JsThrow x) {
-        visitElement(x);
-    }
+    public open fun visitThrow(x: JsThrow): Unit =
+            visitElement(x)
 
-    public void visitTry(JsTry x) {
-        visitElement(x);
-    }
+    public open fun visitTry(x: JsTry): Unit =
+            visitElement(x)
 
-    public void visit(JsVar x) {
-        visitElement(x);
-    }
+    public open fun visit(x: JsVar): Unit =
+            visitElement(x)
 
-    public void visitVars(JsVars x) {
-        visitElement(x);
-    }
+    public open fun visitVars(x: JsVars): Unit =
+            visitElement(x)
 
-    public void visitWhile(JsWhile x) {
-        visitElement(x);
-    }
+    public open fun visitWhile(x: JsWhile): Unit =
+            visitElement(x)
 
-    public void visitDocComment(JsDocComment comment) {
-        visitElement(comment);
-    }
+    public open fun visitDocComment(comment: JsDocComment): Unit =
+            visitElement(comment)
 
-    protected void visitElement(JsNode node) {
+    protected open fun visitElement(node: JsNode) {
     }
 }
\ No newline at end of file