[Solved] What will be the output of this Kafka consumer poll loop snippet if no messages are available?while (true) { var records = consumer.poll(Duration.ofMillis(100)); System.out.println(records.count());... | Kafka

Kafka - Consumers

What will be the output of this Kafka consumer poll loop snippet if no messages are available?

while (true) {
  var records = consumer.poll(Duration.ofMillis(100));
  System.out.println(records.count());
  break;
}

A0

Bnull

CException thrown

DInfinite loop with no output

Step-by-Step Solution

Solution:

Step 1: Understand poll() returns empty records if none available
If no messages are available, poll() returns an empty ConsumerRecords object, not null or exception.
Step 2: Check records.count() output
Calling count() on empty records returns 0, which is printed before break ends loop.
Final Answer:
0 -> Option A
Quick Check:
poll() empty records count = 0 [OK]

Quick Trick: poll() returns empty records, count() is zero if no messages [OK]

Common Mistakes:

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What will be the output of this Kafka consumer poll loop snippet if no messages are available?