[Solved] What is the output of this Kafka Streams processor code if the input record value is null?stream.mapValues(value -> { try { return value.toLowerCase(); } catch (Exception e) { return "error"; } }); | Kafka

Kafka - Advanced Stream Processing

What is the output of this Kafka Streams processor code if the input record value is null?

stream.mapValues(value -> {
  try {
    return value.toLowerCase();
  } catch (Exception e) {
    return "error";
  }
});

AException thrown, stream stops

Bnull

C"NULL"

D"error"

Step-by-Step Solution

Solution:

Step 1: Trace code with null input
Calling toLowerCase() on null throws NullPointerException caught by catch block.
Step 2: Check catch block return value
Catch block returns string "error" when exception occurs.
Final Answer:
"error" -> Option D
Quick Check:
Exception caught returns "error" [OK]

Quick Trick: Catch exceptions to return fallback values [OK]

Common Mistakes:

MISTAKES

Master "Advanced Stream Processing" in Kafka

9 interactive learning modes - each teaches the same concept differently

More Kafka Quizzes

What is the output of this Kafka Streams processor code if the input record value is null?