/*
* Copyright (c) 2016, 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;
import java.util.List;
/**
* A simple implementation of the TreeVisitor for ECMAScript edition 6.
*
* <p>The visit methods corresponding to ES 6 language constructs walk the
* "components" of the given tree by calling accept method passing the
* current visitor and the additional parameter.
*
* <p>For constructs introduced in later versions, {@code visitUnknown}
* is called instead which throws {@link UnknownTreeException}.
*
* <p> Methods in this class may be overridden subject to their
* general contract. Note that annotating methods in concrete
* subclasses with {@link java.lang.Override @Override} will help
* ensure that methods are overridden as intended.
*
* @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.
*/
public class SimpleTreeVisitorES6<R, P> extends SimpleTreeVisitorES5_1<R, P> {
@Override
public R visitCompilationUnit(final CompilationUnitTree node, final P r) {
final ModuleTree mod = node.getModule();
if (mod != null) {
mod.accept(this, r);
}
return super.visitCompilationUnit(node, r);
}
/**
* Visit Module tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitModule(final ModuleTree node, final P p) {
node.getImportEntries().forEach(e -> visitImportEntry(e, p));
node.getLocalExportEntries().forEach(e -> visitExportEntry(e, p));
node.getIndirectExportEntries().forEach(e -> visitExportEntry(e, p));
node.getStarExportEntries().forEach(e -> visitExportEntry(e, p));
return null;
}
/**
* Visit Module ExportEntry tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitExportEntry(final ExportEntryTree node, final P p) {
return null;
}
/**
* Visit Module ImportEntry tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitImportEntry(final ImportEntryTree node, final P p) {
return null;
}
/**
* Visit class statement tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitClassDeclaration(final ClassDeclarationTree node, final P p) {
node.getName().accept(this, p);
final ExpressionTree heritage = node.getClassHeritage();
if (heritage != null) {
heritage.accept(this, p);
}
final PropertyTree constructor = node.getConstructor();
if (constructor != null) {
constructor.accept(this, p);
}
final List<? extends PropertyTree> elements = node.getClassElements();
if (elements != null) {
for (final PropertyTree prop : elements) {
prop.accept(this, p);
}
}
return null;
}
/**
* Visit class expression tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitClassExpression(final ClassExpressionTree node, final P p) {
node.getName().accept(this, p);
final ExpressionTree heritage = node.getClassHeritage();
if (heritage != null) {
heritage.accept(this, p);
}
final PropertyTree constructor = node.getConstructor();
if (constructor != null) {
constructor.accept(this, p);
}
final List<? extends PropertyTree> elements = node.getClassElements();
if (elements != null) {
for (final PropertyTree prop : elements) {
prop.accept(this, p);
}
}
return null;
}
/**
* Visit for..of statement tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitForOfLoop(final ForOfLoopTree node, final P p) {
node.getVariable().accept(this, p);
node.getExpression().accept(this, p);
final StatementTree stat = node.getStatement();
if (stat != null) {
stat.accept(this, p);
}
return null;
}
/**
* Visit 'yield' expression tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitYield(final YieldTree node, final P p) {
node.getExpression().accept(this, p);
return null;
}
/**
* Visit 'spread' expression tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitSpread(final SpreadTree node, final P p) {
node.getExpression().accept(this, p);
return null;
}
/**
* Visit template literal tree.
*
* @param node node being visited
* @param p extra parameter passed to the visitor
* @return value from the visitor
*/
@Override
public R visitTemplateLiteral(final TemplateLiteralTree node, final P p) {
final List<? extends ExpressionTree> expressions = node.getExpressions();
for (final ExpressionTree expr : expressions) {
expr.accept(this, p);
}
return null;
}
@Override
public R visitVariable(final VariableTree node, final P r) {
final ExpressionTree expr = node.getBinding();
if (expr != null) {
expr.accept(this, r);
}
super.visitVariable(node, r);
return null;
}
}