Dynamic Contents In SQLite Query And Error Because It Is Not Final

I'm trying to execute SQLite query like this:

final String gender = new String();
if (sexCombo.getValue().toString().equals("Man")) {
gender = "1";
}
else {
gender = "0";
}
final string Q = "INSERT INTO ... VALUES (...., " + gender + "...)");
stmt.executeUpdate(Q);

The problem is:

error: local variables referenced from a lambda expression must be final or effectively final stmt.executeUpdate(Q);

How can I generate query command using conditionals and make it work?