1、创建数据库连接对象
Connection connection=DriverManager.getConnection("jdbc:mysql://localhost:3306/database","root","12345");
2、创建Statement对象
Statement statement=connection.createStatement();
3、执行sql语句,返回ResultSet对象
ResultSet result=statement.executeQuery("select * from user");
4、关闭数据库连接
connection.close();