jdbc数据库连接

1、比如sun公司开发的java链接数据库方法：class connection{public Connection getConnection（url，username，password）；//抽象方法由sun公司实现}DiverManger.getConnection();建立java与数据库链接JDBC接口和数据库厂商的实现：DriverManger接口：加载驱动Connection 接口：建立连接statement 接口：编译sql语句

3、public class Demo3 {public static void main(String[] args) {try {Class.forName("com.mysql.jdbc.Driver");} catch (ClassNotFoundException e) {System.out.println("加载失败！");}Connection con=null;Statement stmt=null;ResultSet rs=null;try {

5、import java.io.IOException;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.util.Properties;/*** * @author Administrator* */public class DBUtil {private static Properties properties = new Properties();private static String driver = null;private static String url = null;private static String username = null;private static String password = null;