Java tutorial
/* * eGov SmartCity eGovernance suite aims to improve the internal efficiency,transparency, * accountability and the service delivery of the government organizations. * * Copyright (C) 2017 eGovernments Foundation * * The updated version of eGov suite of products as by eGovernments Foundation * is available at http://www.egovernments.org * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see http://www.gnu.org/licenses/ or * http://www.gnu.org/licenses/gpl.html . * * In addition to the terms of the GPL license to be adhered to in using this * program, the following additional terms are to be complied with: * * 1) All versions of this program, verbatim or modified must carry this * Legal Notice. * Further, all user interfaces, including but not limited to citizen facing interfaces, * Urban Local Bodies interfaces, dashboards, mobile applications, of the program and any * derived works should carry eGovernments Foundation logo on the top right corner. * * For the logo, please refer http://egovernments.org/html/logo/egov_logo.png. * For any further queries on attribution, including queries on brand guidelines, * please contact contact@egovernments.org * * 2) Any misrepresentation of the origin of the material is prohibited. It * is required that all modified versions of this material be marked in * reasonable ways as different from the original version. * * 3) This license does not grant any rights to any user of the program * with regards to rights under trademark law for use of the trade names * or trademarks of eGovernments Foundation. * * In case of any queries, you can reach eGovernments Foundation at contact@egovernments.org. * */ package org.egov.infra.persistence.validator; import org.apache.commons.lang3.reflect.FieldUtils; import org.egov.infra.exception.ApplicationRuntimeException; import org.egov.infra.persistence.validator.annotation.UniqueDateOverlap; import org.hibernate.Criteria; import org.hibernate.Session; import org.hibernate.criterion.Conjunction; import org.hibernate.criterion.Disjunction; import org.hibernate.criterion.Projections; import org.hibernate.criterion.Restrictions; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import javax.validation.ConstraintValidator; import javax.validation.ConstraintValidatorContext; import java.util.Date; import static org.egov.infra.utils.DateUtils.endOfDay; import static org.egov.infra.utils.DateUtils.startOfDay; public class UniqueDateOverlapValidator implements ConstraintValidator<UniqueDateOverlap, Object> { private UniqueDateOverlap uniqueDateOverlap; @PersistenceContext private EntityManager entityManager; @Override public void initialize(final UniqueDateOverlap uniqueDateOverlap) { this.uniqueDateOverlap = uniqueDateOverlap; } @Override public boolean isValid(Object object, ConstraintValidatorContext context) { try { boolean isValid = checkUnique(object); if (!isValid) context.buildConstraintViolationWithTemplate(uniqueDateOverlap.message()) .addPropertyNode(uniqueDateOverlap.fromField()).addConstraintViolation(); return isValid; } catch (final IllegalAccessException e) { throw new ApplicationRuntimeException("Error while validating unique key with date overlapping", e); } } private boolean checkUnique(Object object) throws IllegalAccessException { Number id = (Number) FieldUtils.readField(object, uniqueDateOverlap.id(), true); Criteria uniqueDateOverlapChecker = entityManager.unwrap(Session.class).createCriteria(object.getClass()) .setReadOnly(true); Conjunction uniqueCheck = Restrictions.conjunction(); for (String fieldName : uniqueDateOverlap.uniqueFields()) { Object fieldValue = FieldUtils.readField(object, fieldName, true); if (fieldValue instanceof String) uniqueCheck.add(Restrictions.eq(fieldName, fieldValue).ignoreCase()); else uniqueCheck.add(Restrictions.eq(fieldName, fieldValue)); } Date fromDate = startOfDay((Date) FieldUtils.readField(object, uniqueDateOverlap.fromField(), true)); Date toDate = endOfDay((Date) FieldUtils.readField(object, uniqueDateOverlap.toField(), true)); Conjunction checkFromDate = Restrictions.conjunction(); checkFromDate.add(Restrictions.le(uniqueDateOverlap.fromField(), fromDate)); checkFromDate.add(Restrictions.ge(uniqueDateOverlap.toField(), fromDate)); Conjunction checkToDate = Restrictions.conjunction(); checkToDate.add(Restrictions.le(uniqueDateOverlap.fromField(), toDate)); checkToDate.add(Restrictions.ge(uniqueDateOverlap.toField(), toDate)); Conjunction checkFromAndToDate = Restrictions.conjunction(); checkFromAndToDate.add(Restrictions.ge(uniqueDateOverlap.fromField(), fromDate)); checkFromAndToDate.add(Restrictions.le(uniqueDateOverlap.toField(), toDate)); Disjunction dateRangeChecker = Restrictions.disjunction(); dateRangeChecker.add(checkFromDate).add(checkToDate).add(checkFromAndToDate); uniqueCheck.add(dateRangeChecker); if (id != null) uniqueCheck.add(Restrictions.ne(uniqueDateOverlap.id(), id)); return uniqueDateOverlapChecker.add(uniqueCheck).setProjection(Projections.id()).setMaxResults(1) .uniqueResult() == null; } }