001/**
002The contents of this file are subject to the Mozilla Public License Version 1.1 
003(the "License"); you may not use this file except in compliance with the License. 
004You may obtain a copy of the License at http://www.mozilla.org/MPL/ 
005Software distributed under the License is distributed on an "AS IS" basis, 
006WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the 
007specific language governing rights and limitations under the License. 
008
009The Original Code is "PredicateMessageRule.java".  Description: 
010"MessageRule that validates using predicates" 
011
012The Initial Developer of the Original Code is University Health Network. Copyright (C) 
0132012.  All Rights Reserved. 
014
015Contributor(s): ______________________________________. 
016
017Alternatively, the contents of this file may be used under the terms of the 
018GNU General Public License (the "GPL"), in which case the provisions of the GPL are 
019applicable instead of those above.  If you wish to allow use of your version of this 
020file only under the terms of the GPL and not to allow others to use your version 
021of this file under the MPL, indicate your decision by deleting  the provisions above 
022and replace  them with the notice and other provisions required by the GPL License.  
023If you do not delete the provisions above, a recipient may use your version of 
024this file under either the MPL or the GPL. 
025 */
026package ca.uhn.hl7v2.validation.builder;
027
028import ca.uhn.hl7v2.model.Message;
029import ca.uhn.hl7v2.validation.ValidationException;
030import ca.uhn.hl7v2.validation.impl.AbstractMessageRule;
031
032/**
033 * Abstract base class for message rules that are evaluated using predicates
034 * 
035 * @author Christian Ohr
036 */
037@SuppressWarnings("serial")
038public abstract class PredicateMessageRule extends AbstractMessageRule implements
039                PredicateRuleSupport<Message> {
040
041        private Predicate testPredicate;
042        private Expression<Message> testExpression;
043
044    /**
045     * Create a new message rule
046     * @param predicate the predicate to be used for the test
047     * @param expression the expression to be used to extract the message part
048     *                   to be tested
049     */
050        public PredicateMessageRule(Predicate predicate, Expression<Message> expression) {
051                this.testPredicate = predicate;
052                this.testExpression = expression;
053        setDescription(testExpression.getDescription() + " '%s' requires to be "
054                + testPredicate.getDescription());
055        }
056
057        public ValidationException[] apply(Message msg) {
058                try {
059                        Object subject = testExpression.evaluate(msg);
060                        boolean passed = getPredicate().evaluate(subject);
061                        return passed ? passed() : failedWithValue(subject, testExpression.getLocation(msg));
062                } catch (Exception e) {
063                        return failed(e);
064                }
065        }
066
067        public Predicate getPredicate() {
068                return testPredicate;
069        }
070
071
072}