Java tutorial
/* * Copyright 2002-2018 the original author or authors. * * 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 * * https://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.springframework.jdbc.datasource; import java.sql.Connection; import java.sql.Driver; import java.sql.SQLException; import java.util.Properties; import org.springframework.beans.BeanUtils; import org.springframework.lang.Nullable; import org.springframework.util.Assert; /** * Simple implementation of the standard JDBC {@link javax.sql.DataSource} interface, * configuring a plain old JDBC {@link java.sql.Driver} via bean properties, and * returning a new {@link java.sql.Connection} from every {@code getConnection} call. * * <p><b>NOTE: This class is not an actual connection pool; it does not actually * pool Connections.</b> It just serves as simple replacement for a full-blown * connection pool, implementing the same standard interface, but creating new * Connections on every call. * * <p>In a Java EE container, it is recommended to use a JNDI DataSource provided by * the container. Such a DataSource can be exposed as a DataSource bean in a Spring * ApplicationContext via {@link org.springframework.jndi.JndiObjectFactoryBean}, * for seamless switching to and from a local DataSource bean like this class. * * <p>If you need a "real" connection pool outside of a Java EE container, consider * <a href="https://commons.apache.org/proper/commons-dbcp">Apache Commons DBCP</a> * or <a href="https://sourceforge.net/projects/c3p0">C3P0</a>. * Commons DBCP's BasicDataSource and C3P0's ComboPooledDataSource are full * connection pool beans, supporting the same basic properties as this class * plus specific settings (such as minimal/maximal pool size etc). * * @author Juergen Hoeller * @since 2.5.5 * @see DriverManagerDataSource */ public class SimpleDriverDataSource extends AbstractDriverBasedDataSource { @Nullable private Driver driver; /** * Constructor for bean-style configuration. */ public SimpleDriverDataSource() { } /** * Create a new DriverManagerDataSource with the given standard Driver parameters. * @param driver the JDBC Driver object * @param url the JDBC URL to use for accessing the DriverManager * @see java.sql.Driver#connect(String, java.util.Properties) */ public SimpleDriverDataSource(Driver driver, String url) { setDriver(driver); setUrl(url); } /** * Create a new DriverManagerDataSource with the given standard Driver parameters. * @param driver the JDBC Driver object * @param url the JDBC URL to use for accessing the DriverManager * @param username the JDBC username to use for accessing the DriverManager * @param password the JDBC password to use for accessing the DriverManager * @see java.sql.Driver#connect(String, java.util.Properties) */ public SimpleDriverDataSource(Driver driver, String url, String username, String password) { setDriver(driver); setUrl(url); setUsername(username); setPassword(password); } /** * Create a new DriverManagerDataSource with the given standard Driver parameters. * @param driver the JDBC Driver object * @param url the JDBC URL to use for accessing the DriverManager * @param conProps the JDBC connection properties * @see java.sql.Driver#connect(String, java.util.Properties) */ public SimpleDriverDataSource(Driver driver, String url, Properties conProps) { setDriver(driver); setUrl(url); setConnectionProperties(conProps); } /** * Specify the JDBC Driver implementation class to use. * <p>An instance of this Driver class will be created and held * within the SimpleDriverDataSource. * @see #setDriver */ public void setDriverClass(Class<? extends Driver> driverClass) { this.driver = BeanUtils.instantiateClass(driverClass); } /** * Specify the JDBC Driver instance to use. * <p>This allows for passing in a shared, possibly pre-configured * Driver instance. * @see #setDriverClass */ public void setDriver(@Nullable Driver driver) { this.driver = driver; } /** * Return the JDBC Driver instance to use. */ @Nullable public Driver getDriver() { return this.driver; } @Override protected Connection getConnectionFromDriver(Properties props) throws SQLException { Driver driver = getDriver(); String url = getUrl(); Assert.notNull(driver, "Driver must not be null"); if (logger.isDebugEnabled()) { logger.debug("Creating new JDBC Driver Connection to [" + url + "]"); } return driver.connect(url, props); } }