1 /*
2 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/expr/DefaultOrExpr.java,v 1.17 2006/11/30 18:49:26 elharo Exp $
3 * $Revision: 1.17 $
4 * $Date: 2006/11/30 18:49:26 $
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: DefaultOrExpr.java,v 1.17 2006/11/30 18:49:26 elharo Exp $
46 */
47
48
49
50 package org.jaxen.expr;
51
52 import org.jaxen.Context;
53 import org.jaxen.JaxenException;
54 import org.jaxen.Navigator;
55 import org.jaxen.function.BooleanFunction;
56
57 class DefaultOrExpr extends DefaultLogicalExpr
58 {
59 /***
60 *
61 */
62 private static final long serialVersionUID = 4894552680753026730L;
63
64 DefaultOrExpr(Expr lhs,
65 Expr rhs)
66 {
67 super( lhs,
68 rhs );
69 }
70
71 public String getOperator()
72 {
73 return "or";
74 }
75
76 public String toString()
77 {
78 return "[(DefaultOrExpr): " + getLHS() + ", " + getRHS() + "]";
79 }
80
81 public Object evaluate(Context context) throws JaxenException
82 {
83 Navigator nav = context.getNavigator();
84 Boolean lhsValue = BooleanFunction.evaluate( getLHS().evaluate( context ), nav );
85
86 if ( lhsValue.booleanValue() )
87 {
88 return Boolean.TRUE;
89 }
90
91 // Short circuits are required in XPath. "The right operand is not
92 // evaluated if the left operand evaluates to true."
93 Boolean rhsValue = BooleanFunction.evaluate( getRHS().evaluate( context ), nav );
94
95 if ( rhsValue.booleanValue() )
96 {
97 return Boolean.TRUE;
98 }
99
100 return Boolean.FALSE;
101 }
102
103 }