当你编写kafka Producer时， 会生成KeyedMessage对象。KeyedMessage<K, V> keyedMessage = new KeyedMessage<>(topicName, key, message)
这里的key值可以为空，在这种情况下， kafka会将这个消息发送到哪个分区上呢？依据Kafka官方的文档， 默认的分区类会随机挑选一个分区：
The third property "partitioner.class" defines what class to use to determine which Partition in the Topic the message is to be sent to. This is optional, but for any non-trivial implementation you are going to want to implement a partitioning scheme. More about the implementation of this class later. If you include a value for the key but haven't defined a partitioner.class Kafka will use the default partitioner. If the key is null, then the Producer will assign the message to a random Partition.
但是这句话相当的误导人。
这里的key值可以为空，在这种情况下， kafka会将这个消息发送到哪个分区上呢？依据Kafka官方的文档， 默认的分区类会随机挑选一个分区：
The third property "partitioner.class" defines what class to use to determine which Partition in the Topic the message is to be sent to. This is optional, but for any non-trivial implementation you are going to want to implement a partitioning scheme. More about the implementation of this class later. If you include a value for the key but haven't defined a partitioner.class Kafka will use the default partitioner. If the key is null, then the Producer will assign the message to a random Partition.
但是这句话相当的误导人。
温馨提示：内容为网友见解，仅供参考
无其他回答
相似回答
