01: /* ====================================================================
02: * Tea - Copyright (c) 1997-2000 Walt Disney Internet Group
03: * ====================================================================
04: * The Tea Software License, Version 1.1
05: *
06: * Copyright (c) 2000 Walt Disney Internet Group. All rights reserved.
07: *
08: * Redistribution and use in source and binary forms, with or without
09: * modification, are permitted provided that the following conditions
10: * are met:
11: *
12: * 1. Redistributions of source code must retain the above copyright
13: * notice, this list of conditions and the following disclaimer.
14: *
15: * 2. Redistributions in binary form must reproduce the above copyright
16: * notice, this list of conditions and the following disclaimer in
17: * the documentation and/or other materials provided with the
18: * distribution.
19: *
20: * 3. The end-user documentation included with the redistribution,
21: * if any, must include the following acknowledgment:
22: * "This product includes software developed by the
23: * Walt Disney Internet Group (http://opensource.go.com/)."
24: * Alternately, this acknowledgment may appear in the software itself,
25: * if and wherever such third-party acknowledgments normally appear.
26: *
27: * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must
28: * not be used to endorse or promote products derived from this
29: * software without prior written permission. For written
30: * permission, please contact opensource@dig.com.
31: *
32: * 5. Products derived from this software may not be called "Tea",
33: * "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet",
34: * "Kettle", "Trove" or "BeanDoc" appear in their name, without prior
35: * written permission of the Walt Disney Internet Group.
36: *
37: * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38: * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
40: * DISCLAIMED. IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS
41: * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
42: * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
43: * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
44: * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
45: * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
46: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
47: * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
48: * ====================================================================
49: *
50: * For more information about Tea, please see http://opensource.go.com/.
51: */
52:
53: package com.go.tea.parsetree;
54:
55: import com.go.tea.compiler.SourceInfo;
56:
57: /******************************************************************************
58: * A literal is an expression that has a constant value.
59: *
60: * @author Brian S O'Neill
61: * @version
62: * <!--$$Revision:--> 19 <!-- $-->, <!--$$JustDate:--> 9/07/00 <!-- $-->
63: */
64: public abstract class Literal extends Expression {
65: protected Literal(SourceInfo info) {
66: super (info);
67: }
68:
69: public Object accept(NodeVisitor visitor) {
70: return visitor.visit(this );
71: }
72:
73: /**
74: * Usually returns true, but some literals may have an unknown value if
75: * they are converted to another type.
76: */
77: public boolean isValueKnown() {
78: return true;
79: }
80: }
|