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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: 1.4 $ $Date: 2003/08/09 15:49:50 $ 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 // use a TreeSet to ensure that the result is the same for all 123 // runs/implementations. In general, the HashSet should be faster for 124 // individual lookups. 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 } //-- InExpression

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