1 /*
2 * $Header$
3 * $Revision: 1261 $
4 * $Date: 2006-11-30 10:49:27 -0800 (Thu, 30 Nov 2006) $
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: DefaultAndExpr.java 1261 2006-11-30 18:49:27Z elharo $
46 */
47
48 package org.jaxen.expr;
49
50 import org.jaxen.Context;
51 import org.jaxen.JaxenException;
52 import org.jaxen.Navigator;
53 import org.jaxen.function.BooleanFunction;
54
55 class DefaultAndExpr extends DefaultLogicalExpr
56 {
57 /**
58 *
59 */
60 private static final long serialVersionUID = -5237984010263103742L;
61
62 DefaultAndExpr(Expr lhs,
63 Expr rhs)
64 {
65 super( lhs,
66 rhs );
67 }
68
69 public String getOperator()
70 {
71 return "and";
72 }
73
74 public String toString()
75 {
76 return "[(DefaultAndExpr): " + getLHS() + ", " + getRHS() + "]";
77 }
78
79 public Object evaluate(Context context) throws JaxenException
80 {
81 Navigator nav = context.getNavigator();
82 Boolean lhsValue = BooleanFunction.evaluate( getLHS().evaluate( context ), nav );
83
84 if ( !lhsValue.booleanValue() )
85 {
86 return Boolean.FALSE;
87 }
88
89 // Short circuits are required in XPath. "The right operand is not
90 // evaluated if the left operand evaluates to false."
91 Boolean rhsValue = BooleanFunction.evaluate( getRHS().evaluate( context ), nav );
92
93 if ( !rhsValue.booleanValue() )
94 {
95 return Boolean.FALSE;
96 }
97
98 return Boolean.TRUE;
99 }
100
101
102 }