error if retrieved values are null

Hello, i am trying to retrieve the value of a column which can be null but i get a very general message:java.sql.SQLException.

this is the code i use:

try

{

Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");

Connection con = DriverManager.getConnection( "jdbc:odbc:hospital","doctor", "doctor");

PreparedStatement pstmt = con.prepareStatement("SELECT aktinografia.ektimhsh FROM aktinografia WHERE aktinografia.aktin_code = ? ");

pstmt.setInt(1,g2);

ResultSet rset=pstmt.executeQuery();

while(rset.next())

{

str1= rset.getString("ektimhsh");

}

pstmt.close();

con.close();

}

catch(SQLException e)

{

out.print(e);

}

Please help!

Thanks in advance.

[797 byte] By [dados] at [2007-9-26 7:00:21]