Apache Kafka: …StringDeserializer is not an instance of …Deserializer

Question

In my simple application i am trying to instantiate a KafkaConsumer my code is nearly a copy of the code from javadoc (\"Automatic Offset Committing\"):

@Slf4j
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Answer 1

This might be the problem with Kafka classloading.
Setting classloader to null might help.

...
Thread currentThread = Thread.currentThread();    
ClassLoader savedClassLoader = currentThread.getContextClassLoader();

currentThread.setContextClassLoader(null);
KafkaConsumer consumer = new KafkaConsumer<>(props);

currentThread.setContextClassLoader(savedClassLoader);
...

There is full explanation:
https://stackoverflow.com/a/50981469/1673775