1 /*
2 * $Header$
3 * $Revision$
4 * $Date$
5 *
6 * ====================================================================
7 *
8 * Copyright 2000-2002 bob mcwhirter & James Strachan.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions are
13 * met:
14 *
15 * * Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 *
18 * * Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 *
22 * * Neither the name of the Jaxen Project nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
27 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
29 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
30 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
31 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
32 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
33 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
34 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
35 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
36 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 *
38 * ====================================================================
39 * This software consists of voluntary contributions made by many
40 * individuals on behalf of the Jaxen Project and was originally
41 * created by bob mcwhirter <bob@werken.com> and
42 * James Strachan <jstrachan@apache.org>. For more information on the
43 * Jaxen Project, please see <http://www.jaxen.org/>.
44 *
45 * $Id$
46 */
47
48
49
50 package org.jaxen.expr;
51
52 import java.util.List;
53
54 abstract class DefaultTruthExpr extends DefaultBinaryExpr
55 {
56 DefaultTruthExpr(Expr lhs,
57 Expr rhs)
58 {
59 super( lhs,
60 rhs );
61 }
62
63 @Override
64 public String toString()
65 {
66 return "[(DefaultTruthExpr): " + getLHS() + ", " + getRHS() + "]";
67 }
68
69 protected boolean bothAreSets(Object lhs,
70 Object rhs)
71 {
72 return ( lhs instanceof List
73 &&
74 rhs instanceof List );
75 }
76
77 protected boolean eitherIsSet(Object lhs,
78 Object rhs)
79 {
80 return ( lhs instanceof List
81 ||
82 rhs instanceof List );
83 }
84
85 protected boolean isSet(Object obj)
86 {
87 return ( obj instanceof List );
88 }
89
90 protected boolean isBoolean(Object obj)
91 {
92 return ( obj instanceof Boolean );
93 }
94
95 protected boolean setIsEmpty( List<?> set )
96 {
97 return (set == null || set.isEmpty());
98 }
99
100 protected boolean eitherIsBoolean(Object lhs,
101 Object rhs)
102 {
103 return ( lhs instanceof Boolean
104 ||
105 rhs instanceof Boolean );
106 }
107
108 protected boolean bothAreBoolean(Object lhs,
109 Object rhs)
110 {
111 return ( lhs instanceof Boolean
112 &&
113 rhs instanceof Boolean );
114 }
115
116 protected boolean eitherIsNumber(Object lhs,
117 Object rhs)
118 {
119 return ( lhs instanceof Number
120 ||
121 rhs instanceof Number );
122 }
123
124 }
125