Make serdes final
@@ -62,7 +62,7 @@ public class EmailService implements Service {
final GlobalKTable<Long, Customer> customers = builder.globalTable(CUSTOMERS.name(),
Consumed.with(CUSTOMERS.keySerde(), CUSTOMERS.valueSerde()));
- Joined<String, Order, Payment> serdes = Joined
+ final Joined<String, Order, Payment> serdes = Joined
.with(ORDERS.keySerde(), ORDERS.valueSerde(), PAYMENTS.valueSerde());
//Join the two streams and the table then send an email for each
