package dao; import java.sql.*; public class BaseDao {  //oracle // private  static final String Dirver="oracle.jdbc.driver.OracleDriver"; // private  static final String URL="jdbc:oracle:thin:@localhost:1521:XE"; // private  static final String name="admin"; // private  static final String pass="123";  //sqlserver // private static final String Dirver="com.microsoft.sqlserver.jdbc.SQLServerDriver"; // private static final String URL="jdbc:sqlserver://localhost:1433;DatabaseName=TBLdb"; // private static final String name="sa"; // private static final String pass="sa";  //mysql  private static final String Dirver="com.mysql.jdbc.Driver";  private static final String URL="jdbc:mysql://127.0.0.1:3306/school";  private static final String name="root";  private static final String pass="123456";  public  Connection getCconnection()  {   Connection conn=null;   try {    Class.forName(Dirver);    conn=DriverManager.getConnection(URL,name,pass);   } catch (Exception e) {    e.printStackTrace();   }   return conn;  }  public void closAll(Connection conn,PreparedStatement ps,ResultSet rs)  {   try {    if(null!=rs)     rs.close();    if(null!=ps)     ps.close();    if(null!=conn)     conn.close();   } catch (Exception e) {    e.printStackTrace();   }  }  public int executeUpdate(String sql,String parms[])  {   Connection conn=null;   PreparedStatement ps=null;   int result=-1;   try {    conn=getCconnection();    ps=conn.prepareStatement(sql);    if(null!=parms){     for(int i=0;i<parms.length;i++){      ps.setString(i+1,parms[i]);     }    }    result=ps.executeUpdate();    execute();   } catch (Exception e) {    System.out.println(e.getMessage());   }finally{    closAll(conn, ps, null);   }   return result;  }   public static void main(String[] args)throws Exception  {   BaseDao b=new BaseDao();   Connection con=b.getCconnection();   System.out.println(con.isClosed());  } }