public boolean connectDB() {
		String driver = "com.mysql.jdbc.Driver";
		String url = "jdbc:mysql://" + this.ip + ":" + this.port + "/" + this.dbName;
		try {
		     // 
		     Class.forName(driver);
		     // ݿ
		     conn = DriverManager.getConnection(url, this.user, this.password);
		     return conn.isClosed();
		} catch(ClassNotFoundException e) {   
	    	 System.out.println("Sorry,can`t find the Driver!");   
	    	 e.printStackTrace();   
	    	 return false;
    	} catch(SQLException e) {   
    		 e.printStackTrace();  
    		 return false;
    	} catch(Exception e) {   
    		 e.printStackTrace();   
    		 return false;
    	}   
	}