package cn.com.dao;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import javax.naming.Context;import javax.naming.InitialContext;import javax.sql.DataSource;public class BaseDAO {public static final String driver = "com.mysql.jdbc.Driver";public static final String url = "jdbc:mysql://localhost:3306/easybuy?useUnicode=true&charaterEncoding=UTF-8";public static final String username = "root";public static final String pwd = "1234";public Connection con=null;public PreparedStatement ps=null;public ResultSet rs=null;    //获取连接getConnectionpublic Connection getConnection() throws Exception {//加载驱动        Class.forName(driver);if (con == null || con.isClosed()) {
            con = DriverManager.getConnection(url, username, pwd);
        }return con;
    }//查询 executeQuerypublic ResultSet executeQuery(String sql, Object...objects) throws Exception {
        con = getConnection();
        ps = con.prepareStatement(sql);for (int i = 0; i < objects.length; i++) {
            ps.setObject(i + 1, objects[i]);
        }
        rs = ps.executeQuery();return rs;
    }//增、删、改public int executeUpudate(String sql, Object... objects) throws Exception {
        con = getConnection();
        ps = con.prepareStatement(sql);for (int i = 0; i < objects.length; i++) {
            ps.setObject(i + 1, objects[i]);
        }int num = ps.executeUpdate();        return num;
    }public void closeAll() throws Exception {if (rs != null || !rs.isClosed()) {
            rs.close();
        }if (ps != null || !ps.isClosed()) {
            ps.close();
        }if (con != null || !con.isClosed()) {
            con.close();
        }
    }
}

   select(String name,String pwd)  Exception;

}

  UserDaoImpl  BaseDAO   select(String name,String pwd) ="select count(1) from easybuy_user where loginname=? and loginname=?"=(rs!==rs.getInt("id"

   select(String name,String pwd)