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 "ValidationExceptionHandler.java".  Description: 
010"Interface for handling violations during the validation process." 
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;
027
028import ca.uhn.hl7v2.HL7Exception;
029
030/**
031 * Handler that is called for every violation during a message validation.
032 * <p>
033 * Instances of this class are NOT thread safe as they collect data during the
034 * validation process.
035 * 
036 * @author Christian Ohr
037 */
038public interface ValidationExceptionHandler<R> {
039
040    /**
041     * Called in case of validation rule violations.
042     * @param exceptions the exceptions that describe the validatin errors
043     */
044    void onExceptions(ValidationException... exceptions);
045
046    /**
047     * Returns an overall validation result based on an aggregation of all
048     * exceptions thrown during the validation process. Often, this is a simple
049     * value indicating if any ValidationException has been thrown, but it can
050     * also be a complete response message that reflects the validation results.
051     *
052     * @return the validation result
053     * @throws HL7Exception if an error occurred during calculating the result
054     */
055    R result() throws HL7Exception;
056
057        /**
058         * Should be called before validation starts. Some ValidationHandler implementations
059         * may need context information of the subject being validated
060         * 
061         * @param subject subject to be validated
062         */
063        void setValidationSubject(Object subject);
064
065    /**
066     * Returns a boolean flag indicating whether a validation was successful or not.
067     * This is independent of {@link #result()} which may return a more complex
068     * object.
069     * @return true if the validation is considered to be failed.
070     */
071        boolean hasFailed();
072
073}