Java tutorial
/** * * Copyright (C) 2002-2012 "SYSNET International, Inc." * support@sysnetint.com [http://www.sysnetint.com] * * This file is part of OpenEMPI. * * OpenEMPI is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) 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 Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.openhie.openempi.dao.hibernate; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.openhie.openempi.dao.GenericDao; import org.springframework.orm.ObjectRetrievalFailureException; import org.springframework.orm.hibernate3.support.HibernateDaoSupport; import java.io.Serializable; import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; /** * This class serves as the Base class for all other DAOs - namely to hold * common CRUD methods that they might all use. You should only need to extend * this class when your require custom CRUD logic. * * <p>To register this class in your Spring context file, use the following XML. * <pre> * <bean id="fooDao" class="org.openhie.openempi.dao.hibernate.GenericDaoHibernate"> * <constructor-arg value="org.openhie.openempi.model.Foo"/> * <property name="sessionFactory" ref="sessionFactory"/> * </bean> * </pre> * * @author <a href="mailto:bwnoll@gmail.com">Bryan Noll</a> * @param <T> a type variable * @param <PK> the primary key for that type */ public class GenericDaoHibernate<T, PK extends Serializable> extends HibernateDaoSupport implements GenericDao<T, PK> { /** * Log variable for all child classes. Uses LogFactory.getLog(getClass()) from Commons Logging */ protected final Log log = LogFactory.getLog(getClass()); private Class<T> persistentClass; /** * Constructor that takes in a class to see which type of entity to persist * @param persistentClass the class type you'd like to persist */ public GenericDaoHibernate(final Class<T> persistentClass) { this.persistentClass = persistentClass; } /** * {@inheritDoc} */ @SuppressWarnings("unchecked") public List<T> getAll() { return super.getHibernateTemplate().loadAll(this.persistentClass); } /** * {@inheritDoc} */ @SuppressWarnings("unchecked") public List<T> getAllDistinct() { Collection result = new LinkedHashSet(getAll()); return new ArrayList(result); } /** * {@inheritDoc} */ @SuppressWarnings("unchecked") public T get(PK id) { T entity = (T) super.getHibernateTemplate().get(this.persistentClass, id); if (entity == null) { log.warn("Uh oh, '" + this.persistentClass + "' object with id '" + id + "' not found..."); throw new ObjectRetrievalFailureException(this.persistentClass, id); } return entity; } /** * {@inheritDoc} */ @SuppressWarnings("unchecked") public boolean exists(PK id) { T entity = (T) super.getHibernateTemplate().get(this.persistentClass, id); return entity != null; } /** * {@inheritDoc} */ @SuppressWarnings("unchecked") public T save(T object) { return (T) super.getHibernateTemplate().merge(object); } /** * {@inheritDoc} */ public void remove(PK id) { super.getHibernateTemplate().delete(this.get(id)); } /** * {@inheritDoc} */ @SuppressWarnings("unchecked") public List<T> findByNamedQuery(String queryName, Map<String, Object> queryParams) { String[] params = new String[queryParams.size()]; Object[] values = new Object[queryParams.size()]; int index = 0; Iterator<String> i = queryParams.keySet().iterator(); while (i.hasNext()) { String key = i.next(); params[index] = key; values[index++] = queryParams.get(key); } return getHibernateTemplate().findByNamedQueryAndNamedParam(queryName, params, values); } }