Java tutorial
/* * Licensed to The Apereo Foundation under one or more contributor license * agreements. See the NOTICE file distributed with this work for * additional information regarding copyright ownership. * * The Apereo Foundation licenses this file to you 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 * distributed 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 the specific language governing permissions and * limitations under the License. * */ package org.unitime.commons.hibernate.util; import java.io.File; import java.net.URL; import java.net.URLDecoder; import java.sql.Connection; import java.sql.SQLException; import java.sql.Statement; import java.util.Hashtable; import java.util.Iterator; import java.util.Map; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.dom4j.Document; import org.dom4j.Element; import org.dom4j.io.SAXReader; import org.hibernate.Query; import org.hibernate.QueryException; import org.hibernate.Session; import org.hibernate.Transaction; import org.hibernate.jdbc.Work; import org.unitime.commons.Debug; import org.unitime.timetable.ApplicationProperties; import org.unitime.timetable.defaults.ApplicationProperty; import org.unitime.timetable.model.ApplicationConfig; import org.unitime.timetable.model.dao._RootDAO; /** * Process resource given by application property tmtbl.db.update (defaults to file dbupdate.xml) * and the update database accordingly. * * @author Tomas Muller, Stephanie Schluttenhofer * */ public abstract class DatabaseUpdate { protected static Log sLog = LogFactory.getLog(DatabaseUpdate.class); private Element iRoot = null; private String iDialectSQL = null; protected abstract String findDbUpdateFileName(); protected abstract String versionParameterName(); protected abstract String updateName(); protected DatabaseUpdate(Document document) throws Exception { if (!"dbupdate".equals(document.getRootElement().getName())) throw new Exception("Unknown format."); iRoot = document.getRootElement(); } protected DatabaseUpdate() throws Exception { Document document = null; String dbUpdateFile = findDbUpdateFileName(); URL dbUpdateFileUrl = ApplicationProperties.class.getClassLoader().getResource(dbUpdateFile); if (dbUpdateFileUrl != null) { Debug.info("Reading " + URLDecoder.decode(dbUpdateFileUrl.getPath(), "UTF-8") + " ..."); document = (new SAXReader()).read(dbUpdateFileUrl.openStream()); } else if (new File(dbUpdateFile).exists()) { Debug.info("Reading " + dbUpdateFile + " ..."); document = (new SAXReader()).read(new File(dbUpdateFile)); } if (document == null) { sLog.error("Unable to execute " + updateName() + " database auto-update, reason: resource " + dbUpdateFile + " not found."); return; } if (!"dbupdate".equals(document.getRootElement().getName())) throw new Exception("Unknown format."); iRoot = document.getRootElement(); } public int getVersion() { return Integer.parseInt(ApplicationConfig.getConfigValue(versionParameterName(), "0")); } public void performUpdate() { sLog.info("Current " + updateName() + " database version: " + getVersion()); String dialect = _RootDAO.getConfiguration().getProperty("dialect"); for (Iterator i = iRoot.elementIterator("dialect"); i.hasNext();) { Element dialectElement = (Element) i.next(); if (dialect.equals(dialectElement.getTextTrim())) iDialectSQL = dialectElement.attributeValue("type"); } for (Iterator i = iRoot.elementIterator("update"); i.hasNext();) { Element updateElement = (Element) i.next(); int updateVersion = Integer.parseInt(updateElement.attributeValue("version")); if (updateVersion > getVersion() && !performUpdate(updateElement)) break; } sLog.info("New " + updateName() + " database version: " + getVersion()); } public boolean performUpdate(Element updateElement) { int version = Integer.parseInt(updateElement.attributeValue("version")); Session hibSession = new _RootDAO().getSession(); String schema = _RootDAO.getConfiguration().getProperty("default_schema"); Transaction tx = null; Hashtable variables = new Hashtable(); try { tx = hibSession.beginTransaction(); sLog.info(" Performing " + updateName() + " update to version " + version + " (" + updateElement.attributeValue("comment") + ")"); for (Iterator i = updateElement.elementIterator(); i.hasNext();) { Element queryElement = (Element) i.next(); String type = queryElement.getName(); String query = queryElement.getText().trim().replaceAll("%SCHEMA%", schema); for (Iterator j = variables.entrySet().iterator(); j.hasNext();) { Map.Entry entry = (Map.Entry) j.next(); query = query.replaceAll("%" + entry.getKey() + "%", entry.getValue().toString()); } String condition = queryElement.attributeValue("condition", "none"); String action = queryElement.attributeValue("action", "next"); String value = queryElement.attributeValue("value"); String into = queryElement.attributeValue("into"); if (queryElement.attribute("onFail") != null) { condition = "fail"; action = queryElement.attributeValue("onFail"); } if (queryElement.attribute("onEqual") != null) { condition = "equal"; action = queryElement.attributeValue("onEqual"); } if (queryElement.attribute("onNotEqual") != null) { condition = "notEqual"; action = queryElement.attributeValue("onNotEqual"); } if (query.length() == 0) continue; try { if (type.equals("hql") || type.equals("sql") || type.equals(iDialectSQL)) { sLog.debug(" -- HQL: " + query + " (con:" + condition + ", act:" + action + ", val:" + value + ")"); Query q = null; try { q = (type.equals("hql") ? hibSession.createQuery(query) : hibSession.createSQLQuery(query)); } catch (QueryException e) { // Work-around Hibernate issue HHH-2697 (https://hibernate.onjira.com/browse/HHH-2697) if (!"hql".equals(type)) { final String sql = query; hibSession.doWork(new Work() { @Override public void execute(Connection connection) throws SQLException { Statement statement = connection.createStatement(); int lines = statement.executeUpdate(sql); sLog.debug(" -- " + lines + " lines affected."); statement.close(); } }); } else throw e; } boolean ok = true; if (into != null) { variables.put(into, q.uniqueResult().toString()); } else if ("equal".equals(condition) && value != null) { ok = value.equals(q.uniqueResult().toString()); } else if ("notEqual".equals(condition) && value != null) { ok = !value.equals(q.uniqueResult().toString()); } else if (q != null) { int lines = q.executeUpdate(); sLog.debug(" -- " + lines + " lines affected."); if ("noChange".equals(condition)) ok = (lines == 0); else if ("change".equals(condition)) ok = (lines > 0); } if (ok) { if ("next".equals(action)) continue; if ("done".equals(action)) break; if ("fail".equals(action)) { sLog.error("Update to " + updateName() + " version " + version + " failed (condition not met for query '" + query + "', con:" + condition + ", act:" + action + ", val:" + value + ")."); tx.rollback(); return false; } } } else { sLog.debug(" -- skip: " + query + " (con:" + condition + ", act:" + action + ", val:" + value + ")"); } } catch (Exception e) { sLog.warn("Query '" + query + "' failed, " + e.getMessage(), e); if (e.getCause() != null && e.getCause().getMessage() != null) sLog.warn("Cause: " + e.getCause().getMessage()); if ("fail".equals(condition)) { if ("next".equals(action)) continue; if ("done".equals(action)) break; } sLog.error("Update to version " + version + " failed."); tx.rollback(); return false; } } ApplicationConfig versionCfg = ApplicationConfig.getConfig(versionParameterName()); if (versionCfg == null) { versionCfg = new ApplicationConfig(versionParameterName()); versionCfg.setDescription("Timetabling " + updateName() + " DB version (do not change -- this is used by automatic database update)"); } versionCfg.setValue(String.valueOf(version)); hibSession.saveOrUpdate(versionCfg); sLog.info(" " + updateName() + " Database version increased to: " + version); if (tx != null && tx.isActive()) tx.commit(); HibernateUtil.clearCache(); return true; } catch (Exception e) { if (tx != null && tx.isActive()) tx.rollback(); sLog.error("Update to version " + version + " failed, reason:" + e.getMessage(), e); return false; } } public static void update() { try { new UniTimeCoreDatabaseUpdate().performUpdate(); String additionalUpdates = ApplicationProperty.DatabaseUpdateAddonClass.value(); if (additionalUpdates != null && !additionalUpdates.trim().isEmpty()) { DatabaseUpdate du = (DatabaseUpdate) (Class.forName(additionalUpdates).newInstance()); ; du.performUpdate(); } } catch (Exception e) { sLog.error("Unable to execute database auto-update, reason: " + e.getMessage(), e); } finally { _RootDAO.closeCurrentThreadSessions(); } } }