Java tutorial
/* * Copyright 2011-2012 Brian Matthews * * 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 * 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 com.btmatthews.maven.plugins.inmemdb.db.derby; import com.btmatthews.maven.plugins.inmemdb.Loader; import com.btmatthews.maven.plugins.inmemdb.MessageUtil; import com.btmatthews.maven.plugins.inmemdb.db.AbstractSQLDatabase; import com.btmatthews.maven.plugins.inmemdb.ldr.dbunit.DBUnitCSVLoader; import com.btmatthews.maven.plugins.inmemdb.ldr.dbunit.DBUnitFlatXMLLoader; import com.btmatthews.maven.plugins.inmemdb.ldr.dbunit.DBUnitXLSLoader; import com.btmatthews.maven.plugins.inmemdb.ldr.dbunit.DBUnitXMLLoader; import com.btmatthews.maven.plugins.inmemdb.ldr.sqltool.SQLLoader; import com.btmatthews.utils.monitor.Logger; import org.apache.commons.dbcp.BasicDataSource; import org.apache.derby.drda.NetworkServerControl; import org.apache.derby.iapi.reference.Property; import org.codehaus.plexus.util.StringUtils; import javax.sql.DataSource; import java.io.OutputStream; import java.net.InetAddress; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.text.MessageFormat; import java.util.HashMap; import java.util.Map; /** * Implements support for in-memory Apache Derby databases. * * @author <a href="mailto:brian@btmatthews.com">Brian Matthews</a> * @version 1.0.0 */ public final class DerbyDatabase extends AbstractSQLDatabase { /** * The connection protocol for in-memory H2 databases. */ private static final String PROTOCOL = "derby://localhost:{0,number,#}/memory:"; /** * Default port Derby listens on, can be altered via setting port property */ private static final int DEFAULT_PORT = 1527; /** * The name of the additional connection parameter which will cause the * database to be created. */ private static final String CREATE = "create"; /** * The name of the additional connection parameter which will cause the * database to be dropped. */ private static final String DROP = "drop"; /** * The value used with the {@link #CREATE} and {@link #DROP} connection parameters. */ private static final String TRUE = "true"; /** * The JDBC driver class name. */ private static final String DRIVER_CLASS = "org.apache.derby.jdbc.ClientDriver"; /** * The loaders that are supported for loading data or executing scripts. */ private static final Loader[] LOADERS = new Loader[] { new DBUnitXMLLoader(), new DBUnitFlatXMLLoader(), new DBUnitCSVLoader(), new DBUnitXLSLoader(), new SQLLoader() }; /** * */ private static final OutputStream DEV_NULL = new OutputStream() { public void write(int b) { } }; /** * The server used to accept connections from other JVMs. */ private NetworkServerControl server; /** * The default constructor initializes the default database port. */ public DerbyDatabase() { super(DEFAULT_PORT); } /** * Get the database connection protocol used for JDBC connections * * @return Returns protocol */ protected String getUrlProtocol() { return MessageFormat.format(PROTOCOL, getPort()); } /** * Get the data source that describes the connection to the in-memory Apache * Derby database. * * @param attributes Additional attributes for the data source connection string. * @return Returns {@code dataSource} which was initialised by the * constructor. */ @Override public DataSource getDataSource() { final BasicDataSource dataSource = new BasicDataSource(); dataSource.setUrl(getUrl(getAttributes())); dataSource.setUsername(getUsername()); if (StringUtils.isNotEmpty(getPassword())) { dataSource.setPassword(getPassword()); } dataSource.setDriverClassName(DRIVER_CLASS); return dataSource; } /** * Get the loaders that are supported for loading data or executing scripts. * * @return Returns {@link #LOADERS}. */ @Override public Loader[] getLoaders() { return LOADERS; } /** * Start the in-memory Apache Derby database. * * @param logger Used to report errors and raise exceptions. */ @Override public void start(final Logger logger) { logger.logInfo("Starting embedded Derby database"); System.setProperty(Property.ERRORLOG_FIELD_PROPERTY, "com.btmatthews.maven.plugins.inmemdb.db.derby.DerbyDatabase.DEV_NULL"); try { server = new NetworkServerControl(InetAddress.getByName("localhost"), getPort()); server.start(null); } catch (final Exception exception) { final String message = MessageUtil.getMessage(ERROR_STARTING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } try { Class.forName(DRIVER_CLASS).newInstance(); } catch (final InstantiationException exception) { final String message = MessageUtil.getMessage(ERROR_STARTING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } catch (final IllegalAccessException exception) { final String message = MessageUtil.getMessage(ERROR_STARTING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } catch (final ClassNotFoundException exception) { final String message = MessageUtil.getMessage(ERROR_STARTING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } final Map<String, String> attributes = new HashMap<String, String>(); attributes.put(CREATE, TRUE); try { final Connection connection = DriverManager.getConnection(getUrl(attributes), getUsername(), getPassword().length() == 0 ? null : getPassword()); connection.close(); } catch (final SQLException exception) { final String message = MessageUtil.getMessage(ERROR_STARTING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } logger.logInfo("Started embedded Derby database"); } /** * Shutdown the in-memory Apache Derby database by opening a connection with * <code>drop=true</code>. If successful this will cause a SQL exception * with a SQL State of 08006 and a vendor specific error code of 45000. * * @param logger Used to report errors and raise exceptions. */ @Override public void stop(final Logger logger) { logger.logInfo("Stopping embedded Derby database"); if (server != null) { final Map<String, String> attributes = new HashMap<String, String>(); attributes.put(DROP, TRUE); try { DriverManager.getConnection(getUrl(attributes), getUsername(), getPassword().length() == 0 ? null : getPassword()); } catch (final SQLException exception) { if (exception.getErrorCode() != 45000 || !"08006".equals(exception.getSQLState())) { final String message = MessageUtil.getMessage(ERROR_STARTING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } } try { server.shutdown(); } catch (final Exception exception) { final String message = MessageUtil.getMessage(ERROR_STOPPING_SERVER, getDatabaseName()); logger.logError(message, exception); return; } } logger.logInfo("Stopped embedded Derby database"); } @Override public boolean isStarted(final Logger logger) { if (server != null) { try { server.ping(); return true; } catch (final Exception e) { return false; } } return false; } @Override public boolean isStopped(final Logger logger) { try { server.ping(); return false; } catch (final Exception e) { return true; } } }