JavaSE练习

前言：对Java提供的数据库访问规则（JDBC）进行回顾练习。

一、导入jar包
项目下新建lib包，复制mysql-connector-java-5.1.37-bin.jar 到lib包下。右键buildpath –>Add to buildpath。

二、使用步骤
1.注册驱动.
2.获得连接.
3.获得语句执行平台
4.执行sql语句
5.处理结果
6.释放资源.

三、代码实现

package cn.itcast.javaeevideoday03;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.Statement;/** *  * @author 大家都说名字长不会被发现 * */public class JDBCDemo {    private static String sqlSelect = "select * from person;";    private static String sqlUpdate ="update person set padderss = '北京' where pname = '石破天'";    private static String sqlInsert = "insert into person value (null,'石破天',25,'北京海淀')";    private static String sqlDelete ="delete from person where pid = 6";    public static void main(String[] args) throws Exception {        /*         * 1.注册驱动.         *          * 注册驱动的三种方式         * DriverManager.registerDriver(new com.mysql.jdbc.Driver());            new Driver();            Class.forName("com.mysql.jdbc.Driver");         */        Class.forName("com.mysql.jdbc.Driver");        /*         * 2.获得连接.         */        String url = "jdbc:mysql://localhost:3306/day21";        Connection connection = DriverManager.getConnection(url);        /*         * 3.获得sql语句对象         *          * 获取sql语句对象两种方式         * Statement createStatement = connection.createStatement();         *          * PreparedStatement statement = connection.prepareStatement(sql);         */        PreparedStatement statement = connection.prepareStatement(sqlSelect);        /*         * 4.执行sql语句         *          *         */        //执行插入语句        statement.executeUpdate(sqlInsert);        //执行删除语句        statement.executeUpdate(sqlDelete);        //执行修改语句        statement.executeUpdate(sqlUpdate);        //执行查询语句        ResultSet resultSet = statement.executeQuery();        /*         * 5.处理结果         */        //获取表中的字段数据        while(resultSet.next()) {            int uid = resultSet.getInt("pid");            String uname = resultSet.getString("pname");            int uage = resultSet.getInt("page");            String uadderss = resultSet.getString("padderss");            System.out.println(uid +"  "+uname+"  "+uage+"  "+uadderss);        }        /*         * 6.释放资源.         */        resultSet.close();        statement.close();        connection.close();    }}