public DBConnection(String DB_NUM) throws CustomerizedException{
		ConfigFileReader config = new ConfigFileReader();
		if(config != null){
			this.isTruncate = config.getResourceInfo("TRUNCATE_STATUS");
			if(DB_NUM.equalsIgnoreCase("DB1")){
				this.DriverName = config.getResourceInfo("DB1_DRIVERNAME");
				this.URL = config.getResourceInfo("DB1_URL");
				this.UserName = config.getResourceInfo("DB1_USERNAME");
				this.PassWord = config.getResourceInfo("DB1_PASSWORD");
			}else if(DB_NUM.equalsIgnoreCase("DB2")){
				this.DriverName = config.getResourceInfo("DB2_DRIVERNAME");
				this.URL = config.getResourceInfo("DB2_URL");
				this.UserName = config.getResourceInfo("DB2_USERNAME");
				this.PassWord = config.getResourceInfo("DB2_PASSWORD");
			}else if(DB_NUM.equalsIgnoreCase("DB3")){
				this.DriverName = config.getResourceInfo("DB3_DRIVERNAME");
				this.URL = config.getResourceInfo("DB3_URL");
				this.UserName = config.getResourceInfo("DB3_USERNAME");
				this.PassWord = config.getResourceInfo("DB3_PASSWORD");
			}else if(DB_NUM.equalsIgnoreCase("DB4")){
				this.DriverName = config.getResourceInfo("DB4_DRIVERNAME");
				this.URL = config.getResourceInfo("DB4_URL");
				this.UserName = config.getResourceInfo("DB4_USERNAME");
				this.PassWord = config.getResourceInfo("DB4_PASSWORD");
			}else if(DB_NUM.equalsIgnoreCase("DB5")){
				this.DriverName = config.getResourceInfo("DB5_DRIVERNAME");
				this.URL = config.getResourceInfo("DB5_URL");
				this.UserName = config.getResourceInfo("DB5_USERNAME");
				this.PassWord = config.getResourceInfo("DB5_PASSWORD");
			}else if(DB_NUM.equalsIgnoreCase("DB6")){
				this.DriverName = config.getResourceInfo("DB6_DRIVERNAME");
				this.URL = config.getResourceInfo("DB6_URL");
				this.UserName = config.getResourceInfo("DB6_USERNAME");
				this.PassWord = config.getResourceInfo("DB6_PASSWORD");
			}else{
				throw new CustomerizedException("Only surport 6 DB,you " +
						"must use DB1,DB2,DB3,DB4,DB5,DB6 to change the DB " +
						"you want to connect with!");
			}
		}
	}