Consumer poll loop in Kafka - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to poll messages from the Kafka consumer.

Kafka

ConsumerRecords<String, String> records = consumer.[1](Duration.ofMillis(100));

Drag options to blanks, or click blank then click option'

AcommitSync

Bsubscribe

Cpoll

Dclose

Attempts:

3 left

💡 Hint

Common Mistakes

Using subscribe instead of poll to fetch messages.

Calling commitSync before polling messages.

The poll method is used to fetch data from Kafka topics.

2fill in blank

medium

Complete the code to iterate over the polled records.

Kafka

for (ConsumerRecord<String, String> record : [1]) {
    System.out.println(record.value());
}

Drag options to blanks, or click blank then click option'

Arecords

Bconsumer

Ctopic

Dpartition

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to iterate over the consumer object instead of the records.

Using topic or partition which are not iterable collections.

The records variable holds the polled messages to iterate over.

3fill in blank

hard

Fix the error in committing offsets synchronously after processing records.

Kafka

consumer.[1]();

Drag options to blanks, or click blank then click option'

AcommitAsync

BcommitSync

Cpoll

Dsubscribe

Attempts:

3 left

💡 Hint

Common Mistakes

Using commitAsync when synchronous commit is required.

Calling poll or subscribe instead of commit methods.

commitSync() commits the offsets synchronously to Kafka after processing.

4fill in blank

hard

Fill both blanks to create a consumer poll loop that processes messages and commits offsets.

Kafka

while (true) {
    ConsumerRecords<String, String> records = consumer.[1](Duration.ofMillis(100));
    for (ConsumerRecord<String, String> record : records) {
        System.out.println(record.value());
    }
    consumer.[2]();
}

Drag options to blanks, or click blank then click option'

Apoll

Bsubscribe

CcommitSync

Dclose

Attempts:

3 left

💡 Hint

Common Mistakes

Using subscribe instead of poll to fetch messages.

Using commitAsync instead of commitSync when synchronous commit is needed.

The loop polls messages with poll() and commits offsets synchronously with commitSync().

5fill in blank

hard

Fill all three blanks to create a consumer poll loop that subscribes to a topic, polls messages, and commits offsets.

Kafka

consumer.[1](Collections.singletonList("my-topic"));

while (true) {
    ConsumerRecords<String, String> records = consumer.[2](Duration.ofMillis(100));
    for (ConsumerRecord<String, String> record : records) {
        System.out.println(record.value());
    }
    consumer.[3]();
}

Drag options to blanks, or click blank then click option'

Asubscribe

Bpoll

CcommitSync

Dclose

Attempts:

3 left

💡 Hint

Common Mistakes

Calling poll before subscribe.

Using commitAsync instead of commitSync.

Calling close inside the loop.

The consumer first subscribes to the topic with subscribe(), then polls messages with poll(), and finally commits offsets synchronously with commitSync().