--- /dev/null	2015-03-09 08:23:42.456618816 +0530
+++ new/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/api/tree/TreeVisitor.java	2015-03-09 10:46:43.171168289 +0530
@@ -0,0 +1,438 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.nashorn.api.tree;
+
+/**
+ * A visitor of trees, in the style of the visitor design pattern.
+ * Classes implementing this interface are used to operate
+ * on a tree when the kind of tree is unknown at compile time.
+ * When a visitor is passed to an tree's {@link Tree#accept
+ * accept} method, the <tt>visit<i>XYZ</i></tt> method most applicable
+ * to that tree is invoked.
+ *
+ * <p> Classes implementing this interface may or may not throw a
+ * {@code NullPointerException} if the additional parameter {@code p}
+ * is {@code null}; see documentation of the implementing class for
+ * details.
+ *
+ * <p> <b>WARNING:</b> It is possible that methods will be added to
+ this interface to accommodate new, currently unknown, language
+ structures added to future versions of the ECMAScript programming
+ language. When new visit methods are added for new Tree subtypes,
+ default method bodies will be introduced which will call visitUnknown
+ method as a fallback.
+ *
+ * @param <R> the return type of this visitor's methods.  Use {@link
+ *            Void} for visitors that do not need to return results.
+ * @param <P> the type of the additional parameter to this visitor's
+ *            methods.  Use {@code Void} for visitors that do not need an
+ *            additional parameter.
+ *
+ * @since 1.9
+ */
+@jdk.Exported
+public interface TreeVisitor<R,P> {
+    /**
+     * Visit assignment tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitAssignment(AssignmentTree node, P p);
+    
+    /**
+     * Visit compound assignment tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitCompoundAssignment(CompoundAssignmentTree node, P p);
+    
+    /**
+     * Visit binary expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitBinary(BinaryTree node, P p);
+    
+    /**
+     * Visit block statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitBlock(BlockTree node, P p);
+    
+    /**
+     * Visit break statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitBreak(BreakTree node, P p);
+    
+    /**
+     * Visit case statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitCase(CaseTree node, P p);
+    
+    /**
+     * Visit catch block statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitCatch(CatchTree node, P p);
+    
+    /**
+     * Visit conditional expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitConditionalExpression(ConditionalExpressionTree node, P p);
+    
+    /**
+     * Visit continue statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitContinue(ContinueTree node, P p);
+    
+    /**
+     * Visit debugger statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitDebugger(DebuggerTree node, P p);
+    
+    /**
+     * Visit do-while statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitDoWhileLoop(DoWhileLoopTree node, P p);
+    
+    /**
+     * Visit error expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitErroneous(ErroneousTree node, P p);
+    
+    /**
+     * Visit expression statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitExpressionStatement(ExpressionStatementTree node, P p);
+    
+    /**
+     * Visit 'for' statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitForLoop(ForLoopTree node, P p);
+    
+    /**
+     * Visit for..in statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitForInLoop(ForInLoopTree node, P p);
+    
+    /**
+     * Visit function call expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitFunctionCall(FunctionCallTree node, P p);
+    
+    /**
+     * Visit function declaration tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitFunctionDeclaration(FunctionDeclarationTree node, P p);
+    
+    /**
+     * Visit function expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitFunctionExpression(FunctionExpressionTree node, P p);
+    
+        /**
+     * Visit identifier tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitIdentifier(IdentifierTree node, P p);
+    
+    /**
+     * Visit 'if' statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitIf(IfTree node, P p);
+    
+    /**
+     * Visit array access expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitArrayAccess(ArrayAccessTree node, P p);
+    
+    /**
+     * Visit array literal expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitArrayLiteral(ArrayLiteralTree node, P p);
+    
+    /**
+     * Visit labeled statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitLabeledStatement(LabeledStatementTree node, P p);
+    
+    /**
+     * Visit literal expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitLiteral(LiteralTree node, P p);
+    
+    /**
+     * Visit parenthesized expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitParenthesized(ParenthesizedTree node, P p);
+    
+    /**
+     * Visit return statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitReturn(ReturnTree node, P p);
+    
+    /**
+     * Visit member select expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitMemberSelect(MemberSelectTree node, P p);
+    
+    /**
+     * Visit 'new' expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitNew(NewTree node, P p);
+    
+    /**
+     * Visit object literal tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitObjectLiteral(ObjectLiteralTree node, P p);
+    
+    /**
+     * Visit a property of an object literal expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitProperty(PropertyTree node, P p);
+    
+    /**
+     * Visit regular expression literal tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitRegExpLiteral(RegExpLiteralTree node, P p);
+    
+    /**
+     * Visit an empty statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitEmptyStatement(EmptyStatementTree node, P p);
+    
+    /**
+     * Visit 'switch' statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitSwitch(SwitchTree node, P p);
+    
+    /**
+     * Visit 'throw' expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitThrow(ThrowTree node, P p);
+    
+    /**
+     * Visit compilation unit tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitCompilationUnit(CompilationUnitTree node, P p);
+    
+    /**
+     * Visit 'try' statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitTry(TryTree node, P p);
+    
+    /**
+     * Visit 'instanceof' expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitInstanceOf(InstanceOfTree node, P p);
+    
+    /**
+     * Visit unary expression tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitUnary(UnaryTree node, P p);
+    
+    /**
+     * Visit variable declaration tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitVariable(VariableTree node, P p);
+    
+    /**
+     * Visit 'while' statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitWhileLoop(WhileLoopTree node, P p);
+    
+    /**
+     * Visit 'with' statement tree.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitWith(WithTree node, P p);
+    
+    /**
+     * Visit unknown expression/statement tree. This fallback will be
+     * called if new Tree subtypes are introduced in future. A specific
+     * implementation may throw {{@linkplain UnknownTreeException unknown tree exception}
+     * if the visitor implementation was for an older language version.
+     * 
+     * @param node node being visited
+     * @param p extra parameter passed to the visitor
+     * @return value from the visitor
+     */
+    R visitUnknown(Tree node, P p);
+}