| /* |
| * Copyright 2008 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| * use this file except in compliance with the License. You may obtain a copy of |
| * the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package com.google.gwt.dev.jjs.ast; |
| |
| import com.google.gwt.dev.jjs.SourceInfo; |
| import com.google.gwt.dev.jjs.SourceOrigin; |
| |
| /** |
| * Java null literal expression. |
| */ |
| public class JNullLiteral extends JValueLiteral { |
| |
| public static final JNullLiteral INSTANCE = new JNullLiteral(SourceOrigin.UNKNOWN); |
| |
| private JNullLiteral(SourceInfo sourceInfo) { |
| super(sourceInfo); |
| } |
| |
| @Override |
| public JType getType() { |
| return JReferenceType.NULL_TYPE; |
| } |
| |
| @Override |
| public Object getValueObj() { |
| return null; |
| } |
| |
| @Override |
| public void traverse(JVisitor visitor, Context ctx) { |
| if (visitor.visit(this, ctx)) { |
| } |
| visitor.endVisit(this, ctx); |
| } |
| |
| /** |
| * Note, if this ever becomes not-a-singleton, we'll need to check the |
| * SourceInfo == SourceOrigin.UNKNOWN. |
| */ |
| private Object readResolve() { |
| return INSTANCE; |
| } |
| } |