jdbc测试代码

1.装载相应的数据库的JDBC驱动并进行初始化
2.建立JDBC和数据库之间的Connection连接
3.创建Statement或者PreparedStatement接口，执行SQL语句
4.处理和显示结果
5.释放资源

//第一个jdbc程序
public class JDBCTest {
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        //1.加载驱动
        Class.forName("com.mysql.jdbc.Driver");
        //2.连接信息  用户信息与url
        String url="jdbc:mysql://localhost:3306/jdbcstudy?useUnicode=true&characterEncoding=utf8&useSSL=true";
        String username="root";
        String password="root";

        //3.连接成功  数据库对象  Connection代表数据库
        Connection connection=DriverManager.getConnection(url,username,password);
        //4.执行sql的对象  statement执行sql对象
        Statement statement = connection.createStatement();
        //5.执行sql  可能存在结果  查看返回结果
        String sql="select * from users";
        //返回的结果集  结果集中封装了全部的查询结果
        ResultSet resultSet = statement.executeQuery(sql);
        while (resultSet.next()){
            System.out.print("id="+resultSet.getObject("id"));
            System.out.print("  name="+resultSet.getObject("name"));
            System.out.print("  pwd="+resultSet.getObject("password"));
            System.out.print("  email="+resultSet.getObject("email"));
            System.out.println("  birthday="+resultSet.getObject("birthday"));
            System.out.println("===========================");
        }
        //6.释放连接
        resultSet.close();
        statement.close();
        connection.close();
    }
}

id=1  name=zhangsan  pwd=123456  email=zs@sina.com  birthday=1980-12-04
===========================
id=2  name=lisi  pwd=123456  email=lisi@sina.com  birthday=1981-12-04
===========================
id=3  name=wangwu  pwd=123456  email=wangwu@sina.com  birthday=1979-12-04
===========================

进程已结束，退出代码 0