/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Rhino code, released
* May 6, 1999.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Steve Yegge
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
* the GPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replacing
* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript.ast;
import org.mozilla.javascript.Token;
/**
* AST node for keyword literals: currently, {@code this},
* {@code null}, {@code true}, {@code false}, and {@code debugger}.
* Node type is one of
* {@link Token#THIS},
* {@link Token#NULL},
* {@link Token#TRUE},
* {@link Token#FALSE}, or
* {@link Token#DEBUGGER}.
*/
public class KeywordLiteral extends AstNode {
public KeywordLiteral() {
}
public KeywordLiteral(int pos) {
super(pos);
}
public KeywordLiteral(int pos, int len) {
super(pos, len);
}
/**
* Constructs a new KeywordLiteral
* @param nodeType the token type
*/
public KeywordLiteral(int pos, int len, int nodeType) {
super(pos, len);
setType(nodeType);
}
/**
* Sets node token type
* @throws IllegalArgumentException if {@code nodeType} is unsupported
*/
@Override
public KeywordLiteral setType(int nodeType) {
if (!(nodeType == Token.THIS
|| nodeType == Token.NULL
|| nodeType == Token.TRUE
|| nodeType == Token.FALSE
|| nodeType == Token.DEBUGGER))
throw new IllegalArgumentException("Invalid node type: "
+ nodeType);
type = nodeType;
return this;
}
/**
* Returns true if the token type is {@link Token#TRUE} or
* {@link Token#FALSE}.
*/
public boolean isBooleanLiteral() {
return type == Token.TRUE || type == Token.FALSE;
}
@Override
public String toSource(int depth) {
StringBuilder sb = new StringBuilder();
sb.append(makeIndent(depth));
switch (getType()) {
case Token.THIS:
sb.append("this");
break;
case Token.NULL:
sb.append("null");
break;
case Token.TRUE:
sb.append("true");
break;
case Token.FALSE:
sb.append("false");
break;
case Token.DEBUGGER:
sb.append("debugger");
break;
default:
throw new IllegalStateException("Invalid keyword literal type: "
+ getType());
}
return sb.toString();
}
/**
* Visits this node. There are no children to visit.
*/
@Override
public void visit(NodeVisitor v) {
v.visit(this);
}
}