When a Spring Boot service needs to talk to another service without waiting on a synchronous HTTP call, message queues are the usual answer. Apache Kafka has become the default choice for this in most backend teams, but a lot of tutorials stop at a "hello world" producer and consumer that would never survive a real production load. Things like consumer retries, error handling, serialization of real objects, and graceful shutdown get skipped, and those are exactly the parts that page you at 2 a.m.
In this tutorial, you will build a Spring Boot application that produces and consumes JSON messages over Kafka. You will configure a producer and a consumer, send a typed object instead of a plain string, handle deserialization errors so one bad message does not block your whole consumer group, and verify the whole thing works end to end. By the end, you will have a small but realistic messaging setup you can build on.
Prerequisites
To follow along, you will need:
Java 17 or later installed. You can check your version by running java -version.
