1 /***
2 * Redistribution and use of this software and associated documentation
3 * ("Software"), with or without modification, are permitted provided
4 * that the following conditions are met:
5 *
6 * 1. Redistributions of source code must retain copyright
7 * statements and notices. Redistributions must also contain a
8 * copy of this document.
9 *
10 * 2. Redistributions in binary form must reproduce the
11 * above copyright notice, this list of conditions and the
12 * following disclaimer in the documentation and/or other
13 * materials provided with the distribution.
14 *
15 * 3. The name "Exolab" must not be used to endorse or promote
16 * products derived from this Software without prior written
17 * permission of Exoffice Technologies. For written permission,
18 * please contact info@exolab.org.
19 *
20 * 4. Products derived from this Software may not be called "Exolab"
21 * nor may "Exolab" appear in their names without prior written
22 * permission of Exoffice Technologies. Exolab is a registered
23 * trademark of Exoffice Technologies.
24 *
25 * 5. Due credit should be given to the Exolab Project
26 * (http://www.exolab.org/).
27 *
28 * THIS SOFTWARE IS PROVIDED BY EXOFFICE TECHNOLOGIES AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
32 * EXOFFICE TECHNOLOGIES OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39 * OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Copyright 2000-2001,2003 (C) Exoffice Technologies Inc. All Rights Reserved.
42 */
43
44 package org.exolab.jms.selector;
45
46 import java.util.HashSet;
47 import java.util.Iterator;
48 import java.util.TreeSet;
49
50 import javax.jms.Message;
51
52
53 /***
54 * This class implements an 'in' expression.
55 * This is an expression that returns a boolean if a identifier's value is one
56 * a set of supplied values. If the identifier is null (undefined), then the
57 * expression evaluates to null.
58 *
59 * @version $Revision: 1.1 $ $Date: 2004/11/26 01:50:44 $
60 * @author <a href="mailto:tma@netspace.net.au">Tim Anderson</a>
61 * @see Expression
62 * @see IdentifierExpression
63 * @see SBool
64 */
65 class InExpression extends IdentifierExpression {
66
67 /***
68 * The set of values to compare against
69 */
70 private final HashSet _values;
71
72
73 /***
74 * Construct a new <code>InExpression</code>
75 *
76 * @param ident the identifier
77 * @param values the values to check against
78 */
79 public InExpression(final Identifier ident, final HashSet values) {
80 super(ident);
81 _values = values;
82 }
83
84 /***
85 * Evaluate the expression
86 *
87 * @param msg the message to use to obtain any header identifier and
88 * property values
89 * @return the evaluated result, or <code>null</code> if the value of the
90 * expression is unknown
91 * @throws TypeMismatchException if the expression tries to evaluate
92 * mismatched types.
93 */
94 public final SObject evaluate(final Message msg)
95 throws TypeMismatchException {
96 SBool result = null;
97
98 SString value = TypeCaster.castToString(identifier().evaluate(msg),
99 "in expression");
100 if (value != null) {
101 if (_values.contains(value.getObject())) {
102 result = SBool.TRUE;
103 } else {
104 result = SBool.FALSE;
105 }
106 }
107 return result;
108 }
109
110 /***
111 * Return a string representation of this expression.
112 *
113 * @return a string representation of this expression
114 */
115 public final String toString() {
116 StringBuffer result = new StringBuffer();
117 result.append('(');
118 result.append(identifier().toString());
119 result.append(" in (");
120 int i = 0;
121 TreeSet sorted = new TreeSet(_values);
122
123
124
125 for (Iterator iter = sorted.iterator(); iter.hasNext(); i++) {
126 if (i > 0) {
127 result.append(", ");
128 }
129 result.append("'");
130 result.append((String) iter.next());
131 result.append("'");
132 }
133 result.append("))");
134 return result.toString();
135 }
136
137 }