利用Java如何实现动态加载数据库驱动

package com.tongtongxue.dynamic.service.impl;import java.net.URL;import java.net.URLClassLoader;import java.sql.Connection;import java.sql.Driver;import java.sql.DriverManager;import java.util.HashMap;import java.util.Map;import java.util.Properties;import javax.annotation.PostConstruct;import org.springframework.stereotype.Service;import com.tongtongxue.dynamic.model.DataSourceInfo;import com.tongtongxue.dynamic.service.IDynamicLoaderService;@Servicepublic class DynamicLoaderService implements IDynamicLoaderService { // 保存数据库连接信息 private Map>String, DataSourceInfo< dataSourceInfos = null;  // 保存数据库相应驱动JAR的路径 private Map>String, String< paths = null; // 缓存对应的Driver对象 private Map>String, Driver< drivers = null; private URLClassLoader classLoader;     @PostConstruct  public void init() throws Exception {   dataSourceInfos = new HashMap>String, DataSourceInfo<();      // 此处只已oracle9和oracle12为例，其它数据库信息同理的方式增加即可   DataSourceInfo oracle9Info = new DataSourceInfo();   oracle9Info.setDriver("oracle.jdbc.driver.OracleDriver");   oracle9Info.setUrl("jdbc:oracle:thin:@192.168.0.101:1521:ORACLE");   oracle9Info.setUsername("system");   oracle9Info.setPassword("system");   dataSourceInfos.put("oracle9", oracle9Info);   DataSourceInfo oracle12Info = new DataSourceInfo();   oracle12Info.setDriver("oracle.jdbc.driver.OracleDriver");   oracle12Info.setUrl("jdbc:oracle:thin:@192.168.0.102:1521:orcl");   oracle12Info.setUsername("system");   oracle12Info.setPassword("system");   dataSourceInfos.put("oracle12", oracle12Info);   // 将数据库对应驱动jar放置容器中   paths = new HashMap>String, String<();   paths.put("oracle9", "/driver/ojdbc14.jar");   paths.put("oracle12", "/driver/ojdbc7.jar");   // 初始化drivers   drivers = new HashMap>String, Driver<();  } @Override public Connection getConnection(String dbType) throws Exception { Connection conn = null; Driver driver = drivers.get(dbType);  DataSourceInfo dataSourceInfo = dataSourceInfos.get(dbType); if (driver == null) {  URL jarUrl = this.getClass().getResource(paths.get(dbType));  classLoader = new URLClassLoader(new URL[]{jarUrl});  Class>&#63;< driverClass = classLoader.loadClass(dataSourceInfo.getDriver());  driver = (Driver) driverClass.newInstance();     drivers.put(dbType, driver); } // 注册驱动 DriverManager.registerDriver(driver); Properties properties = new Properties(); properties.put("user", dataSourceInfo.getUsername());   properties.put("password", dataSourceInfo.getPassword());    conn = DriverManager.getConnection(dataSourceInfo.getUrl(), properties);   // 卸载驱动   DriverManager.deregisterDriver(driver);    return conn; }}