SQL Server DatabaseMetaData getcolumns is not returning column default value

Hi 

I am using the mySQL version 6.0.1 with Spring.  I have a stored procedure defined with default values  in my SQL server 2014 standard version. 

SQLServerDatabaseMetaData  get columns method returns all columns information except default value which is always null. Appreciate if i can get some insight on it 

@event_id varchar(25) = 'INITIATED',

reading default value of a column

rs.getString("COLUMN_DEF")

what am i missing here