How to get an Integer from a Java ResultSet

By default, ResultSet.getInt(...) only returns an int. If the database value is null, it will return 0. This is already covered in the documentation: "The default for ResultSet.getInt when the field value is NULL is to return 0". This is also the case for resultset.getFloat().

This irritating behavior can easily be fixed with the wasNull method:

Integer myInt = resultSet.getInt("nullable_column"); //Returns 0 even if the value should be null
if (resultSet.wasNull()) {
 myInt = null;

This way, your resultSet.getInt(...) will correctly set null values instead of returning 0.