连接数据库的步骤

1.加载驱动程序 Class.forName("oracle.jdbc.driver.OracleDriver"); 2. 建立连接 Connection conn = DriverMananger.getConnection("jdbc:oracle:thin:@127.0.0.1:1521:xe","用户名","密码"); 3 执行查询4 关闭数据库连接

/连接之前，先现在驱动mysql-connector-java-3.1.12.zip解压把其中的//mysql-connector-java-3.1.12-bin.jar加入到项目中import java.sql.*;public class DbUtil {   public static void main(String[] args){       String driver = "com.mysql.jdbc.Driver";     //驱动       String url = "jdbc:MySql://localhost/login"; //数据库URL       String user="root";                          //数据库登录名       String password = "mysql";                   //数据库密码 try { Class.forName(driver); Connection dcon = DriverManager.getConnection(url,user,password); String sql = "select * from login;"; Statement stmt = dcon.createStatement();    ResultSet rs = stmt.executeQuery(sql);      while(rs.next())        {     System.out.print("id:"+rs.getInt("id")+",姓名："+rs.getString("name"));        }    }  catch (Exception e)   { e.printStackTrace(); }}}