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The Unix time number is zero at the Unix epoch, and increases by exactly 86,400 per day since the epoch. Thus 2004-09-16T00:00:00Z, 12,677 days after the epoch, is represented by the Unix time number 12,677 × 86,400 = 1095292800. This can be extended backwards from the epoch too, using negative numbers; thus 1957-10-04T00:00:00Z, 4,472 days before the epoch, is represented by the Unix time number −4,472 × 86,400 = −386380800.

Writing data generated nowadays wouldn't result in the negative timestamp. This is useful if clients are setting record timestamp manually in order to do a lookup by that timestamp later.

Public Interfaces

• org.apache.kafka.common.record
• org.apache.kafka.clients.producer
• org.apache.kafka.streams.processor

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