day39-Spring 13-Spring的JDBC模板：默认连接池的配置-白红宇

day39-Spring 13-Spring的JDBC模板：默认连接池的配置

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发布时间：2019-06-09

本文共 16887 字，大约阅读时间需要 56 分钟。

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 getConnection call. * * NOTE: This class is not an actual connection pool; it does not actually * pool Connections. It just serves as simple replacement for a full-blown * connection pool, implementing the same standard interface, but creating new * Connections on every call. * * 
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 Connection.close() calls will * simply close the Connection, so any DataSource-aware persistence code should work. * * 
NOTE: Within special class loading environments such as OSGi, this class * is effectively superseded by {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). * * 
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). * * 
If you need a "real" connection pool outside of a J2EE container, consider * Apache's Jakarta Commons DBCP * or C3P0. * 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 pre-registered 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.     * 
NOTE: DriverManagerDataSource is primarily intended for accessing     * pre-registered JDBC drivers. 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.     * 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 getConnectionFromDriver,     * 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 getConnectionFromDriver,     * 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.     * 
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;

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 hierarchy17:26:03,595  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 hierarchy17:26:03,633  INFO DriverManagerDataSource:153 - Loaded JDBC driver: com.mysql.jdbc.Driver17:26:03,998  INFO GenericApplicationContext:1042 - Closing org.springframework.context.support.GenericApplicationContext@1fa78298: startup date [Fri May 05 17:26:03 CST 2017]; root of context hierarchy17:26:03,999  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))");    }}

转载于:https://www.cnblogs.com/ZHONGZHENHUA/p/6813465.html

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