day39-Spring 13-Spring的JDBC模板：默认连接池的配置
Spring内置的连接池DriverManagerDataSource的源码.
/* * Copyright 2002-2008 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 * * 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.springframework.jdbc.datasource; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.util.Properties; import org.springframework.util.Assert; import org.springframework.util.ClassUtils; /** * Simple implementation of the standard JDBC {@link javax.sql.DataSource} interface, * configuring the plain old JDBC {@link java.sql.DriverManager} via bean properties, and * returning a new {@link java.sql.Connection} from every <code>getConnection</code> 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>Useful for test or standalone environments outside of a J2EE container, either * as a DataSource bean in a corresponding ApplicationContext or in conjunction with * a simple JNDI environment. Pool-assuming <code>Connection.close()</code> calls will * simply close the Connection, so any DataSource-aware persistence code should work. * * <p><b>NOTE: Within special class loading environments such as OSGi, this class * is effectively superseded by {@link SimpleDriverDataSource} due to general class * loading issues with the JDBC DriverManager that be resolved through direct Driver * usage (which is exactly what SimpleDriverDataSource does).</b> * * <p>In a J2EE 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. * For tests, you can then either set up a mock JNDI environment through Spring's * {@link org.springframework.mock.jndi.SimpleNamingContextBuilder}, or switch the * bean definition to a local DataSource (which is simpler and thus recommended). * * <p>If you need a "real" connection pool outside of a J2EE container, consider * <a href="http://jakarta.apache.org/commons/dbcp">Apache's Jakarta Commons DBCP</a> * or <a href="http://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 14.03.2003 * @see SimpleDriverDataSource */ public class DriverManagerDataSource extends AbstractDriverBasedDataSource { /** * Constructor for bean-style configuration. */ public DriverManagerDataSource() { } /** * Create a new DriverManagerDataSource with the given JDBC URL, * not specifying a username or password for JDBC access. * @param url the JDBC URL to use for accessing the DriverManager * @see java.sql.DriverManager#getConnection(String) */ public DriverManagerDataSource(String url) { setUrl(url); } /** * Create a new DriverManagerDataSource with the given standard * DriverManager parameters. * @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.DriverManager#getConnection(String, String, String) */ public DriverManagerDataSource(String url, String username, String password) { setUrl(url); setUsername(username); setPassword(password); } /** * Create a new DriverManagerDataSource with the given JDBC URL, * not specifying a username or password for JDBC access. * @param url the JDBC URL to use for accessing the DriverManager * @param conProps JDBC connection properties * @see java.sql.DriverManager#getConnection(String) */ public DriverManagerDataSource(String url, Properties conProps) { setUrl(url); setConnectionProperties(conProps); } /** * Create a new DriverManagerDataSource with the given standard * DriverManager parameters. * @param driverClassName the JDBC driver class name * @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 * @deprecated since Spring 2.5. DriverManagerDataSource is primarily * intended for accessing <i>pre-registered</i> JDBC drivers. * If you need to register a new driver, consider using * {@link SimpleDriverDataSource} instead. */ @Deprecated public DriverManagerDataSource(String driverClassName, String url, String username, String password) { setDriverClassName(driverClassName); setUrl(url); setUsername(username); setPassword(password); } /** * Set the JDBC driver class name. This driver will get initialized * on startup, registering itself with the JDK's DriverManager. * <p><b>NOTE: DriverManagerDataSource is primarily intended for accessing * <i>pre-registered</i> JDBC drivers.</b> If you need to register a new driver, * consider using {@link SimpleDriverDataSource} instead. Alternatively, consider * initializing the JDBC driver yourself before instantiating this DataSource. * The "driverClassName" property is mainly preserved for backwards compatibility, * as well as for migrating between Commons DBCP and this DataSource. * @see java.sql.DriverManager#registerDriver(java.sql.Driver) * @see SimpleDriverDataSource */ public void setDriverClassName(String driverClassName) { Assert.hasText(driverClassName, "Property 'driverClassName' must not be empty"); String driverClassNameToUse = driverClassName.trim(); try { Class.forName(driverClassNameToUse, true, ClassUtils.getDefaultClassLoader()); } catch (ClassNotFoundException ex) { throw new IllegalStateException("Could not load JDBC driver class [" + driverClassNameToUse + "]", ex); } if (logger.isInfoEnabled()) { logger.info("Loaded JDBC driver: " + driverClassNameToUse); } } @Override protected Connection getConnectionFromDriver(Properties props) throws SQLException { String url = getUrl(); if (logger.isDebugEnabled()) { logger.debug("Creating new JDBC DriverManager Connection to [" + url + "]"); } return getConnectionFromDriverManager(url, props); } /** * Getting a Connection using the nasty static from DriverManager is extracted * into a protected method to allow for easy unit testing. * @see java.sql.DriverManager#getConnection(String, java.util.Properties) */ protected Connection getConnectionFromDriverManager(String url, Properties props) throws SQLException { return DriverManager.getConnection(url, props); } }
DriverManagerDataSource的父类AbstractDriverBasedDataSource的源码
/* * Copyright 2002-2008 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 * * 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.springframework.jdbc.datasource; import java.sql.Connection; import java.sql.SQLException; import java.util.Properties; import org.springframework.util.Assert; /** * Abstract base class for JDBC {@link javax.sql.DataSource} implementations * that operate on a JDBC {@link java.sql.Driver}. * * @author Juergen Hoeller * @since 2.5.5 * @see SimpleDriverDataSource * @see DriverManagerDataSource */ public abstract class AbstractDriverBasedDataSource extends AbstractDataSource { private String url; private String username; private String password; private Properties connectionProperties; /** * Set the JDBC URL to use for connecting through the Driver. * @see java.sql.Driver#connect(String, java.util.Properties) */ public void setUrl(String url) { Assert.hasText(url, "Property 'url' must not be empty"); this.url = url.trim(); } /** * Return the JDBC URL to use for connecting through the Driver. */ public String getUrl() { return this.url; } /** * Set the JDBC username to use for connecting through the Driver. * @see java.sql.Driver#connect(String, java.util.Properties) */ public void setUsername(String username) { this.username = username; } /** * Return the JDBC username to use for connecting through the Driver. */ public String getUsername() { return this.username; } /** * Set the JDBC password to use for connecting through the Driver. * @see java.sql.Driver#connect(String, java.util.Properties) */ public void setPassword(String password) { this.password = password; } /** * Return the JDBC password to use for connecting through the Driver. */ public String getPassword() { return this.password; } /** * Specify arbitrary connection properties as key/value pairs, * to be passed to the Driver. * <p>Can also contain "user" and "password" properties. However, * any "username" and "password" bean properties specified on this * DataSource will override the corresponding connection properties. * @see java.sql.Driver#connect(String, java.util.Properties) */ public void setConnectionProperties(Properties connectionProperties) { this.connectionProperties = connectionProperties; } /** * Return the connection properties to be passed to the Driver, if any. */ public Properties getConnectionProperties() { return this.connectionProperties; } /** * This implementation delegates to <code>getConnectionFromDriver</code>, * using the default username and password of this DataSource. * @see #getConnectionFromDriver(String, String) * @see #setUsername * @see #setPassword */ public Connection getConnection() throws SQLException { return getConnectionFromDriver(getUsername(), getPassword()); } /** * This implementation delegates to <code>getConnectionFromDriver</code>, * using the given username and password. * @see #getConnectionFromDriver(String, String) */ public Connection getConnection(String username, String password) throws SQLException { return getConnectionFromDriver(username, password); } /** * Build properties for the Driver, including the given username and password (if any), * and obtain a corresponding Connection. * @param username the name of the user * @param password the password to use * @return the obtained Connection * @throws SQLException in case of failure * @see java.sql.Driver#connect(String, java.util.Properties) */ protected Connection getConnectionFromDriver(String username, String password) throws SQLException { Properties props = new Properties(getConnectionProperties()); if (username != null) { props.setProperty("user", username); } if (password != null) { props.setProperty("password", password); } return getConnectionFromDriver(props); } /** * Obtain a Connection using the given properties. * <p>Template method to be implemented by subclasses. * @param props the merged connection properties * @return the obtained Connection * @throws SQLException in case of failure */ protected abstract Connection getConnectionFromDriver(Properties props) throws SQLException; }
public void setDriverClassName(String driverClassName) { Assert.hasText(driverClassName, "Property 'driverClassName' must not be empty"); String driverClassNameToUse = driverClassName.trim(); try {
public abstract class AbstractDriverBasedDataSource extends AbstractDataSource { private String url; private String username; private String password; private Properties connectionProperties;
<!-- 配置Spring默认的连接池 --> <!-- 这个类由Spring来帮我们创建,它默认情况下只创建一次,因为是单例的. --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver"></property> <property name="url" value="jdbc:mysql:///spring3_day02"></property> <property name="username" value="root"></property> <property name="password" value="123"></property> </bean> <!-- 定义jdbctemplate --> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="dataSource"></property><!-- 把上面定义好的连接池注入进来了 --> </bean>
7:26:03,403 INFO XmlBeanDefinitionReader:315 - Loading XML bean definitions from class path resource [applicationContext.xml]
17:26:03,514 INFO GenericApplicationContext:510 - Refreshing org.springframework.context.support.GenericApplicationContext@1fa78298: startup date [Fri May 05 17:26:03 CST 2017]; root of context hierarchy
17:26:03,595 INFO DefaultListableBeanFactory:577 - Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@63a52fe6: defining beans [dataSource,jdbcTemplate,org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.annotation.ConfigurationClassPostProcessor.importAwareProcessor]; root of factory hierarchy
17:26:03,633 INFO DriverManagerDataSource:153 - Loaded JDBC driver: com.mysql.jdbc.Driver
17:26:03,998 INFO GenericApplicationContext:1042 - Closing org.springframework.context.support.GenericApplicationContext@1fa78298: startup date [Fri May 05 17:26:03 CST 2017]; root of context hierarchy
17:26:03,999 INFO DefaultListableBeanFactory:444 - Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@63a52fe6: defining beans [dataSource,jdbcTemplate,org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.annotation.ConfigurationClassPostProcessor.importAwareProcessor]; root of factory hierarchy
不会把SQL语句打印出来,因为它不是Hibernate.
package cn.itcast.spring3.demo1; import java.sql.DriverManager; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.datasource.DriverManagerDataSource; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import org.springframework.transaction.jta.SpringJtaSynchronizationAdapter; @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration("classpath:applicationContext.xml") public class SpringTest1 { @Autowired @Qualifier("jdbcTemplate") private JdbcTemplate jdbcTemplate;//注入Jdbc模板 @Test public void demo2(){ jdbcTemplate.execute("create table user (id int primary key auto_increment,name varchar(20))"); } @Test public void demo1(){ // 创建连接池: DriverManagerDataSource dataSource = new DriverManagerDataSource();//Spring自带的连接池 // 设置参数: dataSource.setDriverClassName("com.mysql.jdbc.Driver"); dataSource.setUrl("jdbc:mysql:///spring3_day02"); dataSource.setUsername("root"); dataSource.setPassword(""); //使用JDBC的模板: //JdbcTemplate jdbcTemplate = new JdbcTemplate(); //jdbcTemplate.setDataSource(dataSource); JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource); jdbcTemplate.execute("create table user (id int primary key auto_increment,name varchar(20))"); } }
<?xml version="1.0" encoding="UTF-8"?> <!-- 引入beans的头 --> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <!-- 配置Spring默认的连接池 --> <!-- 这个类由Spring来帮我们创建,它默认情况下只创建一次,因为是单例的. --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver"></property> <property name="url" value="jdbc:mysql:///spring3_day02"></property> <property name="username" value="root"></property> <property name="password" value=""></property> </bean> <!-- 定义jdbctemplate --> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="dataSource"></property><!-- 把上面定义好的连接池注入进来了 --> </bean> </beans>
