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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 2000,2003 (C) Exoffice Technologies Inc. All Rights Reserved. 42 */ 43 44 package org.exolab.jms.selector; 45 46 import javax.jms.DeliveryMode; 47 import javax.jms.JMSException; 48 import javax.jms.Message; 49 50 51 /*** 52 * This class implements an identifier. When evaluated, this returns 53 * the value of named header identifier or property, or null if the 54 * identifier is null or the property does not exist. 55 * 56 * @version $Revision: 1.5 $ $Date: 2003/08/10 07:33:39 $ 57 * @author <a href="mailto:tma@netspace.net.au">Tim Anderson</a> 58 * @see org.exolab.jms.selector.Expression 59 * @see org.exolab.jms.selector.Identifiers 60 */ 61 class Identifier implements Expression { 62 63 /*** 64 * The identifier name 65 */ 66 private final String _name; 67 68 /*** 69 * If true the identifier is a header identifier, otherwise it is an user 70 * identifier 71 */ 72 private final boolean _headerField; 73 74 /*** 75 * Persistent delivery mode 76 */ 77 private static final SString PERSISTENT = 78 new SString(Identifiers.PERSISTENT); 79 80 /*** 81 * Non-persistent delivery mode 82 */ 83 private static final SString NON_PERSISTENT = 84 new SString(Identifiers.NON_PERSISTENT); 85 86 87 /*** 88 * Construct a new <code>Identifier</code> 89 * 90 * @param name the identifier name 91 * @throws SelectorException if the identifier cannot be queried by 92 * selectors 93 */ 94 public Identifier(final String name) throws SelectorException { 95 _name = name; 96 97 if (Identifiers.isJMSIdentifier(_name)) { 98 if (!Identifiers.isQueryableJMSIdentifier(_name)) { 99 throw new SelectorException("Invalid header field: " + _name); 100 } 101 _headerField = true; 102 } else { 103 _headerField = false; 104 } 105 } 106 107 /*** 108 * Evaluate the expression 109 * 110 * @param msg the message to use to obtain any header identifier and 111 * property values 112 * @return the evaluated result, or <code>null</code> if the value of the 113 * expression is unknown 114 */ 115 public final SObject evaluate(final Message msg) { 116 SObject value = null; 117 try { 118 if (_headerField) { 119 if (_name.equals(Identifiers.JMS_DELIVERY_MODE)) { 120 value = deliveryMode(msg.getJMSDeliveryMode()); 121 } else if (_name.equals(Identifiers.JMS_PRIORITY)) { 122 value = new SLong(msg.getJMSPriority()); 123 } else if (_name.equals(Identifiers.JMS_TIMESTAMP)) { 124 value = new SLong(msg.getJMSTimestamp()); 125 } else if (_name.equals(Identifiers.JMS_MESSAGE_ID)) { 126 String id = msg.getJMSMessageID(); 127 if (id != null) { 128 value = new SString(id); 129 } 130 } else if (_name.equals(Identifiers.JMS_CORRELATION_ID)) { 131 String id = msg.getJMSCorrelationID(); 132 if (id != null) { 133 value = new SString(id); 134 } 135 } else if (_name.equals(Identifiers.JMS_TYPE)) { 136 String type = msg.getJMSType(); 137 if (type != null) { 138 value = new SString(type); 139 } 140 } 141 } else { 142 value = SObjectFactory.create(msg.getObjectProperty(_name)); 143 } 144 } catch (JMSException ignore) { 145 // do nothing 146 } 147 return value; 148 } 149 150 /*** 151 * Return a string representation of this expression. 152 * 153 * @return a string representation of this expression 154 */ 155 public final String toString() { 156 return _name; 157 } 158 159 /*** 160 * Converts the delivery mode to a string 161 * 162 * @param mode the delivery mode. One of 163 * <code>DeliveryMode.PERSISTENT</code> or 164 * <code>DeliveryMode.NON_PERSISTENT</code> 165 * @return the stringified representation of the delivery mode 166 */ 167 private SString deliveryMode(final int mode) { 168 SString result = PERSISTENT; 169 if (mode == DeliveryMode.NON_PERSISTENT) { 170 result = NON_PERSISTENT; 171 } 172 return result; 173 } 174 175 }

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