java连接数据库步骤

* Connection : 连接数据库并担任传送数据的任务* Statement  : 执行SQL语句* ResultSet  ：保存Statement执行后产生的查询结果1.注册驱动Class.forName（JDBC驱动类）；2.获取数据库连接Connection con=DriverManager.getConnection（JDBC url，数据库用户名，密码）；3.获得 Statement对象Statement stmt=con.createStatement();4.执行SQL语句ResultSet rs=stmt.executeQuery（select a，b from table）；5.处理执行结果while（rs.next()）{   int x=rs.getInt（"a"）；  String s=rs.getString（"b"）；    *数据类型要相匹配}6.释放资源1.rs.close();2.stmt.close();3.con.close();*顺序倒过来依次关闭实例：Java使用PReparedStatement接口插入数据库信息public class PreparedStatementDemo01 {    public static final String DBDRIVER = "org.gjt.mm.MySQL.Driver";    public static final String DBURL = "jdbc:mysql://localhost:3306/";    public static final String DBUSER = "root";    public static final String DBPASS = "root";    public static void main(String args[]) throws ParseException, ClassNotFoundException, SQLException    {        Connection conn = null;    //数据库连接        PreparedStatement pstmt = null;    //数据库操作        Statement stmt = null;        ResultSet rs = null; //Rs接口        String name = "黄鹏";        String passWord = "1598741";        int age = 21;        String sex = "男";        String birthday ="1992-04-30";        Date temp = null;        temp = new SimpleDateFormat("yyyy-MM-dd").parse(birthday);        java.sql.Date bri = new java.sql.Date(temp.getTime());        //创建数据库操作语句        String sql1 = "CREATE DATABASE MyDemo;";         //选择使用哪个数据库的语句        String sql2 = "USE MyDemo;";        //创建数据库表操作语句        String sql3 = "CREATE TABLE user(name varchar(20) primary key,password  varchar(20),age int,sex varchar(10),birthday Date);";        //查询数据库语句        String sql5 = "select * from user;";                            //用PreparedStatement执行的插入语句        String sql4 = "INSERT INTO user(name,password,age,sex,birthday) VALUES(?,?,?,?,?);";                //加载驱动程序        Class.forName(DBDRIVER);        //连接mysql数据库        conn = DriverManager.getConnection(DBURL,DBUSER,DBPASS);            //实例化PreparedStatement        pstmt = conn.prepareStatement(sql4);        //设置第一个?内容        pstmt.setString(1, name);        //设置第二个?内容        pstmt.setString(2, password);        //设置第三个?内容        pstmt.setInt(3, age);        //设置第四个?内容        pstmt.setString(4,sex);        //设置第五个?内容        pstmt.setDate(5, bri);        //执行数据库更新，不需要sql                stmt = conn.createStatement();         stmt.execute(sql1);        stmt.execute(sql2);        stmt.execute(sql3);                pstmt.executeUpdate();        rs = stmt.executeQuery(sql5);        //向控制台输出信息        while(rs.next())         {            String QueryName = rs.getString("name");            String QueryPwd = rs.getString("password");            int QueryAge = rs.getInt("age");            String QuerySex = rs.getString("sex");            Date QueryDate = rs.getDate("birthday");            System.out.println("name:"+QueryName+" pwd:"+QueryPwd+" "+QueryAge+" sex:"+QueryPwd+" date:"+QueryDate);                    }                                            pstmt.close();        conn.close();                    }}