org.apache.kafka.streams.processor.api

Interface RecordMetadata

public interface RecordMetadata

Method Summary

Modifier and Type	Method and Description
long	offset() Return the offset of the current input record; could be -1 if it is not available.
int	partition() Return the partition id of the current input record; could be -1 if it is not available.
String	topic() Return the topic name of the current input record; could be null if it is not available.

Method Detail

topic

String topic()

Return the topic name of the current input record; could be null if it is not available.

For example, if this method is invoked within a @link Punctuator#punctuate(long) punctuation callback}, or while processing a record that was forwarded by a punctuation callback, the record won't have an associated topic. Another example is KTable.transformValues(ValueTransformerWithKeySupplier, String...) (and siblings), that do not always guarantee to provide a valid topic name, as they might be executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.

Returns:

the topic name

partition

int partition()

Return the partition id of the current input record; could be -1 if it is not available.

For example, if this method is invoked within a @link Punctuator#punctuate(long) punctuation callback}, or while processing a record that was forwarded by a punctuation callback, the record won't have an associated partition id. Another example is KTable.transformValues(ValueTransformerWithKeySupplier, String...) (and siblings), that do not always guarantee to provide a valid partition id, as they might be executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.

Returns:

the partition id

offset

long offset()

Return the offset of the current input record; could be -1 if it is not available.

For example, if this method is invoked within a @link Punctuator#punctuate(long) punctuation callback}, or while processing a record that was forwarded by a punctuation callback, the record won't have an associated offset. Another example is KTable.transformValues(ValueTransformerWithKeySupplier, String...) (and siblings), that do not always guarantee to provide a valid offset, as they might be executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.

Returns:

the offset