Java tutorial
// Copyright 2015 The Project Buendia Authors // // Licensed under the Apache License, Version 2.0 (the "License"); you may not // use this file except in compliance with the License. You may obtain a copy // of the License at: http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software distrib- // uted under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES // OR CONDITIONS OF ANY KIND, either express or implied. See the License for // specific language governing permissions and limitations under the License. package org.projectbuendia.openmrs.api.db.hibernate; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.hibernate.Criteria; import org.hibernate.SessionFactory; import org.hibernate.classic.Session; import org.hibernate.criterion.Criterion; import org.hibernate.criterion.Restrictions; import org.hibernate.type.StandardBasicTypes; import org.hibernate.type.Type; import org.openmrs.BaseOpenmrsData; import org.openmrs.Obs; import org.openmrs.Order; import org.openmrs.Patient; import org.projectbuendia.openmrs.api.SyncToken; import org.projectbuendia.openmrs.api.db.ProjectBuendiaDAO; import org.projectbuendia.openmrs.api.db.SyncPage; import org.projectbuendia.openmrs.sync.ObsSyncParameters; import org.projectbuendia.openmrs.sync.OrderSyncParameters; import org.projectbuendia.openmrs.sync.PatientSyncParameters; import org.projectbuendia.openmrs.sync.SyncParameters; import javax.annotation.Nullable; import javax.validation.constraints.Null; import java.util.ArrayList; import java.util.List; import static org.hibernate.criterion.Order.asc; import static org.hibernate.criterion.Restrictions.eq; import static org.hibernate.criterion.Restrictions.in; import static org.hibernate.criterion.Restrictions.ne; import static org.hibernate.criterion.Restrictions.sqlRestriction; /** Default implementation of {@link ProjectBuendiaDAO}. */ public class HibernateProjectBuendiaDAO implements ProjectBuendiaDAO { protected final Log log = LogFactory.getLog(this.getClass()); private SessionFactory sessionFactory; /** @return the sessionFactory */ public SessionFactory getSessionFactory() { return sessionFactory; } /** @param sessionFactory the sessionFactory to set */ public void setSessionFactory(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; } @Override public SyncPage<Obs> getObservationsModifiedAfter(@Nullable SyncToken syncToken, boolean includeVoided, int maxResults) { //noinspection unchecked return fetchSyncPage((Class<SyncParameters<Obs>>) (Class<?>) ObsSyncParameters.class, syncToken, null, includeVoided, maxResults); } @Override public SyncPage<Patient> getPatientsModifiedAfter(@Nullable SyncToken syncToken, boolean includeVoided, int maxResults) { //noinspection unchecked return fetchSyncPage((Class<SyncParameters<Patient>>) (Class<?>) PatientSyncParameters.class, syncToken, null, includeVoided, maxResults); } @Override public SyncPage<Order> getOrdersModifiedAtOrAfter(@Nullable SyncToken syncToken, boolean includeVoided, int maxResults, @Nullable Order.Action[] allowedOrderTypes) { final Criterion itemFilter = allowedOrderTypes != null ? in("action", allowedOrderTypes) : null; //noinspection unchecked return fetchSyncPage((Class<SyncParameters<Order>>) (Class<?>) OrderSyncParameters.class, syncToken, itemFilter, includeVoided, maxResults); } private <T extends BaseOpenmrsData> SyncPage<T> fetchSyncPage(Class<SyncParameters<T>> clazz, @Nullable SyncToken syncToken, Criterion restriction, boolean includeVoided, int maxResults) { List<SyncParameters<T>> dbList = fetchResults(clazz, syncToken, restriction, includeVoided, maxResults); return resultsToSyncPage(dbList); } private <T extends SyncParameters> List<T> fetchResults(Class<T> clazz, @Nullable SyncToken syncToken, @Nullable Criterion restriction, boolean includeVoided, int maxResults) { Session session = sessionFactory.getCurrentSession(); Criteria criteria = session.createCriteria(clazz); if (syncToken != null) { // (a, b) > (x, y) is equivalent to (a > x) OR ((a = x) AND (b > y)). See // http://dev.mysql.com/doc/refman/5.7/en/comparison-operators.html#operator_greater-than criteria.add(sqlRestriction( // {alias} is substituted for the table alias that hibernate uses for the type. "({alias}.date_updated, {alias}.uuid) > (?, ?)", new Object[] { syncToken.greaterThanOrEqualToTimestamp, // If syncToken.greaterThanUuid is null, we use the empty string, which // is 'smaller' than every other string in terms of sort order. syncToken.greaterThanUuid == null ? "" : syncToken.greaterThanUuid }, new Type[] { StandardBasicTypes.TIMESTAMP, StandardBasicTypes.STRING })); } Criteria subCriteria = criteria.createCriteria("item"); if (restriction != null) { subCriteria.add(restriction); } if (!includeVoided) { subCriteria.add(eq("voided", false)); } criteria.addOrder(asc("dateUpdated")).addOrder(asc("uuid")); if (maxResults > 0) { criteria.setMaxResults(maxResults); } //noinspection unchecked return criteria.list(); } private <T extends BaseOpenmrsData> SyncPage<T> resultsToSyncPage(List<SyncParameters<T>> dbResults) { // SyncParameters<T> --> SyncPage<T> ArrayList<T> items = new ArrayList<>(dbResults.size()); for (SyncParameters<T> params : dbResults) { items.add(params.getItem()); } SyncToken token = null; if (dbResults.size() > 0) { SyncParameters<T> lastEntry = dbResults.get(dbResults.size() - 1); token = new SyncToken(lastEntry.getDateUpdated(), lastEntry.getUuid()); } return new SyncPage<>(items, token); } }