Java tutorial
/******************************************************************************* * Copyright 2009, 2010 Innovation Gate GmbH. All Rights Reserved. * * This file is part of the OpenWGA server platform. * * OpenWGA 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 * (at your option) any later version. * * In addition, a special exception is granted by the copyright holders * of OpenWGA called "OpenWGA plugin exception". You should have received * a copy of this exception along with OpenWGA in file COPYING. * If not, see <http://www.openwga.com/gpl-plugin-exception>. * * OpenWGA 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 OpenWGA in file COPYING. * If not, see <http://www.gnu.org/licenses/>. ******************************************************************************/ package de.innovationgate.webgate.api.jdbc; import java.util.ArrayList; import java.util.Arrays; import java.util.Iterator; import java.util.List; import java.util.Map; import org.hibernate.HibernateException; import org.hibernate.Query; import org.hibernate.SQLQuery; import org.hibernate.ScrollableResults; import de.innovationgate.utils.WGUtils; import de.innovationgate.webgate.api.WGAPIException; import de.innovationgate.webgate.api.WGBackendException; import de.innovationgate.webgate.api.WGIteratingResultSetCore; import de.innovationgate.webgate.api.WGResultSetCore; public class WGSQLResultSet extends WGStraightResultSet implements WGResultSetCore, WGIteratingResultSetCore { private List _contents; private WGDatabaseImpl _parent; public WGSQLResultSet(WGDatabaseImpl parent, Query query, Map<String, Object> queryParameters, Map<String, Object> queryOptions) throws WGAPIException { super(parent, query, queryParameters, queryOptions); _parent = parent; //_columnNames = query.getReturnAliases(); Hibernate SQL queries do not support that } private void prepareContentsList() throws WGAPIException, HibernateException { if (_contents == null) { long timeBefore = System.currentTimeMillis(); _contents = wrapEntities(getQuery().iterate()); long timeAfter = System.currentTimeMillis(); setExecutionTime(timeAfter - timeBefore); } } /* (Kein Javadoc) * @see de.innovationgate.webgate.api.WGResultSetCore#getContentList() */ public List getContentList() throws WGAPIException, HibernateException { prepareContentsList(); return _contents; } /* (Kein Javadoc) * @see de.innovationgate.webgate.api.WGResultSetCore#getContentList(int, int) */ public List getContentList(int start, int length) throws WGAPIException, HibernateException { prepareContentsList(); return _contents.subList(start - 1, start - 1 + length); } public boolean isReturnsKeys() { return false; } public Iterator<? extends Object> getResultIterator() { return new HibernateQueryIterator(getQuery(), this); } public int results() throws WGBackendException { try { String query = getQuery().getQueryString(); if (query.contains("{")) { return getEntityQueryResults(query); } else { return getNormalQueryResults(query); } } catch (Exception e) { throw new WGBackendException("Exception retrieving query result size", e); } } private int getNormalQueryResults(String query) { ScrollableResults scroll = getQuery().scroll(); scroll.last(); return (scroll.getRowNumber() + 1); } private int getEntityQueryResults(String query) throws WGAPIException { String querySearchString = WGUtils.clearStrings(query, '\'', 'X').toLowerCase(); int startIdx = querySearchString.indexOf(" from "); // Cannot create count query if we have no regular select/from query if (startIdx == -1) { return 0; } int orderIdx = querySearchString.indexOf("order by"); int groupIdx = querySearchString.toLowerCase().indexOf("group by"); int endIdx = query.length(); if (orderIdx != -1) { endIdx = orderIdx; } if (groupIdx != -1 && groupIdx < endIdx) { endIdx = groupIdx; } String countQueryString = "select count(*) " + query.substring(startIdx, endIdx); countQueryString = WGUtils.strReplace(countQueryString, "{", "", true); countQueryString = WGUtils.strReplace(countQueryString, "}", "", true); SQLQuery countQuery = getParent().getSession().createSQLQuery(countQueryString); injectQueryParams(countQuery, _parameters); return ((Number) countQuery.list().get(0)).intValue(); } @Override public List getColumnNames() throws WGAPIException { return null; } @Override public boolean isLimitingResults() { return false; } }