Java tutorial
/* * iteraplan is an IT Governance web application developed by iteratec, GmbH * Copyright (C) 2004 - 2014 iteratec, GmbH * * This program is free software; you can redistribute it and/or modify it under * the terms of the GNU Affero General Public License version 3 as published by * the Free Software Foundation with the addition of the following permission * added to Section 15 as permitted in Section 7(a): FOR ANY PART OF THE COVERED * WORK IN WHICH THE COPYRIGHT IS OWNED BY ITERATEC, ITERATEC DISCLAIMS THE * WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS. * * 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 Affero General Public License * along with this program; if not, see http://www.gnu.org/licenses or write to * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301 USA. * * You can contact iteratec GmbH headquarters at Inselkammerstr. 4 * 82008 Munich - Unterhaching, Germany, or at email address info@iteratec.de. * * The interactive user interfaces in modified source and object code versions * of this program must display Appropriate Legal Notices, as required under * Section 5 of the GNU Affero General Public License version 3. * * In accordance with Section 7(b) of the GNU Affero General Public License * version 3, these Appropriate Legal Notices must retain the display of the * "iteraplan" logo. If the display of the logo is not reasonably * feasible for technical reasons, the Appropriate Legal Notices must display * the words "Powered by iteraplan". */ package de.iteratec.iteraplan.businesslogic.reports.staticquery; import java.io.BufferedReader; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.commons.io.IOUtils; import de.iteratec.iteraplan.common.Logger; import de.iteratec.iteraplan.common.error.IteraplanErrorMessages; import de.iteratec.iteraplan.common.error.IteraplanTechnicalException; /** * This class provides access to the .properties file which configures the * available static queries. * <p> * This class has been primarily introduced to source out the configuration * of static queries with regard to the open source version of iteraplan. * That way, it is easily possible to configure a subset of static queries. */ public final class PropertiesFacade { private static final Logger LOGGER = Logger.getIteraplanLogger(PropertiesFacade.class); private static final String RESOURCE = "/staticquery.properties"; private static PropertiesFacade instance = null; private static Map<String, String> properties = new HashMap<String, String>(); private static List<String> keys = new ArrayList<String>(); private PropertiesFacade() { // nothing to do. } /** * Returns the singelton instance of this class. On first access, the instance * is created and the properties list is read from the resource specified in the * field {@link PropertiesFacade#RESOURCE} * * @return * See method description. * * @throws IteraplanTechnicalException * If the resource could not be successfully accessed. */ @SuppressWarnings("PMD.AvoidSynchronizedAtMethodLevel") public static synchronized PropertiesFacade getInstance() { if (instance == null) { try { instance = new PropertiesFacade(); instance.init(); } catch (FileNotFoundException ex) { instance = null; LOGGER.error("Cannot access resource + " + RESOURCE); throw new IteraplanTechnicalException(IteraplanErrorMessages.INTERNAL_ERROR, ex); } } return instance; } /** * Reads the properties list from the resource specified in the * field {@link PropertiesFacade#RESOURCE}. * * @throws FileNotFoundException * If the properties file could not be found */ private void init() throws FileNotFoundException { BufferedReader br = null; InputStreamReader inReader = null; final InputStream stream = this.getClass().getResourceAsStream(RESOURCE); if (stream == null) { throw new FileNotFoundException("Properties file '" + RESOURCE + "' not found in classpath."); } try { inReader = new InputStreamReader(stream); br = new BufferedReader(inReader); String line = br.readLine(); while (line != null) { if (!(line.length() == 0 || line.charAt(0) == '#')) { String[] tokens = line.split("="); keys.add(tokens[0]); properties.put(tokens[0], tokens[1]); } line = br.readLine(); } } catch (IOException e) { LOGGER.error("Cannot access resource + " + RESOURCE, e); } finally { IOUtils.closeQuietly(br); IOUtils.closeQuietly(inReader); } } /** * Returns the value of a property with the given key from the properties * list specified in the field {@link PropertiesFacade#RESOURCE}. * * @param key * The key of the property. * * @return * See method description. */ public String getProperty(String key) { return properties.get(key); } /** * Returns a list of all keys in the properties list specified in the * field {@link PropertiesFacade#RESOURCE}. * * @return * See method description. */ public List<String> getAllProperties() { return keys; } }