001/*
002 * Copyright 2002-2015 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.jdbc.datasource;
018
019import java.sql.Connection;
020import java.sql.DriverManager;
021import java.sql.SQLException;
022import java.util.Properties;
023
024import org.springframework.util.Assert;
025import org.springframework.util.ClassUtils;
026
027/**
028 * Simple implementation of the standard JDBC {@link javax.sql.DataSource} interface,
029 * configuring the plain old JDBC {@link java.sql.DriverManager} via bean properties, and
030 * returning a new {@link java.sql.Connection} from every {@code getConnection} call.
031 *
032 * <p><b>NOTE: This class is not an actual connection pool; it does not actually
033 * pool Connections.</b> It just serves as simple replacement for a full-blown
034 * connection pool, implementing the same standard interface, but creating new
035 * Connections on every call.
036 *
037 * <p>Useful for test or standalone environments outside of a J2EE container, either
038 * as a DataSource bean in a corresponding ApplicationContext or in conjunction with
039 * a simple JNDI environment. Pool-assuming {@code Connection.close()} calls will
040 * simply close the Connection, so any DataSource-aware persistence code should work.
041 *
042 * <p><b>NOTE: Within special class loading environments such as OSGi, this class
043 * is effectively superseded by {@link SimpleDriverDataSource} due to general class
044 * loading issues with the JDBC DriverManager that be resolved through direct Driver
045 * usage (which is exactly what SimpleDriverDataSource does).</b>
046 *
047 * <p>In a J2EE container, it is recommended to use a JNDI DataSource provided by
048 * the container. Such a DataSource can be exposed as a DataSource bean in a Spring
049 * ApplicationContext via {@link org.springframework.jndi.JndiObjectFactoryBean},
050 * for seamless switching to and from a local DataSource bean like this class.
051 * For tests, you can then either set up a mock JNDI environment through Spring's
052 * {@link org.springframework.mock.jndi.SimpleNamingContextBuilder}, or switch the
053 * bean definition to a local DataSource (which is simpler and thus recommended).
054 *
055 * <p>If you need a "real" connection pool outside of a J2EE container, consider
056 * <a href="https://commons.apache.org/proper/commons-dbcp">Apache Commons DBCP</a>
057 * or <a href="https://sourceforge.net/projects/c3p0">C3P0</a>.
058 * Commons DBCP's BasicDataSource and C3P0's ComboPooledDataSource are full
059 * connection pool beans, supporting the same basic properties as this class
060 * plus specific settings (such as minimal/maximal pool size etc).
061 *
062 * @author Juergen Hoeller
063 * @since 14.03.2003
064 * @see SimpleDriverDataSource
065 */
066public class DriverManagerDataSource extends AbstractDriverBasedDataSource {
067
068        /**
069         * Constructor for bean-style configuration.
070         */
071        public DriverManagerDataSource() {
072        }
073
074        /**
075         * Create a new DriverManagerDataSource with the given JDBC URL,
076         * not specifying a username or password for JDBC access.
077         * @param url the JDBC URL to use for accessing the DriverManager
078         * @see java.sql.DriverManager#getConnection(String)
079         */
080        public DriverManagerDataSource(String url) {
081                setUrl(url);
082        }
083
084        /**
085         * Create a new DriverManagerDataSource with the given standard
086         * DriverManager parameters.
087         * @param url the JDBC URL to use for accessing the DriverManager
088         * @param username the JDBC username to use for accessing the DriverManager
089         * @param password the JDBC password to use for accessing the DriverManager
090         * @see java.sql.DriverManager#getConnection(String, String, String)
091         */
092        public DriverManagerDataSource(String url, String username, String password) {
093                setUrl(url);
094                setUsername(username);
095                setPassword(password);
096        }
097
098        /**
099         * Create a new DriverManagerDataSource with the given JDBC URL,
100         * not specifying a username or password for JDBC access.
101         * @param url the JDBC URL to use for accessing the DriverManager
102         * @param conProps JDBC connection properties
103         * @see java.sql.DriverManager#getConnection(String)
104         */
105        public DriverManagerDataSource(String url, Properties conProps) {
106                setUrl(url);
107                setConnectionProperties(conProps);
108        }
109
110
111        /**
112         * Set the JDBC driver class name. This driver will get initialized
113         * on startup, registering itself with the JDK's DriverManager.
114         * <p><b>NOTE: DriverManagerDataSource is primarily intended for accessing
115         * <i>pre-registered</i> JDBC drivers.</b> If you need to register a new driver,
116         * consider using {@link SimpleDriverDataSource} instead. Alternatively, consider
117         * initializing the JDBC driver yourself before instantiating this DataSource.
118         * The "driverClassName" property is mainly preserved for backwards compatibility,
119         * as well as for migrating between Commons DBCP and this DataSource.
120         * @see java.sql.DriverManager#registerDriver(java.sql.Driver)
121         * @see SimpleDriverDataSource
122         */
123        public void setDriverClassName(String driverClassName) {
124                Assert.hasText(driverClassName, "Property 'driverClassName' must not be empty");
125                String driverClassNameToUse = driverClassName.trim();
126                try {
127                        Class.forName(driverClassNameToUse, true, ClassUtils.getDefaultClassLoader());
128                }
129                catch (ClassNotFoundException ex) {
130                        throw new IllegalStateException("Could not load JDBC driver class [" + driverClassNameToUse + "]", ex);
131                }
132                if (logger.isInfoEnabled()) {
133                        logger.info("Loaded JDBC driver: " + driverClassNameToUse);
134                }
135        }
136
137
138        @Override
139        protected Connection getConnectionFromDriver(Properties props) throws SQLException {
140                String url = getUrl();
141                if (logger.isDebugEnabled()) {
142                        logger.debug("Creating new JDBC DriverManager Connection to [" + url + "]");
143                }
144                return getConnectionFromDriverManager(url, props);
145        }
146
147        /**
148         * Getting a Connection using the nasty static from DriverManager is extracted
149         * into a protected method to allow for easy unit testing.
150         * @see java.sql.DriverManager#getConnection(String, java.util.Properties)
151         */
152        protected Connection getConnectionFromDriverManager(String url, Properties props) throws SQLException {
153                return DriverManager.getConnection(url, props);
154        }
155
156}