kafka 0.8.x producer Example(scala)

时间:2024-11-21 14:04:25

Producer

最简配置

metadata.broker.list参数指定broker地址,这里不需要填上所有的broker地址,但是如果只写一个,这个broker挂掉后就无法往topic中写入信息,一般写入2-3个broker地址。

serializer.class指定序列化的方式

props.put("metadata.broker.list","broker1:9092,broker2:9092,broker3:9092")
props.put("serializer.class","kafka.serializer.StringEncoder")

producer

两个类型参数,第一个为partition key类型,第二个为消息类型

val producer = new Producer[String,String] (config)

发送消息

KeyedMessage的两个参数,第一个为要写入的topic名字,第二个为要写入的消息。

val date = new KeyedMessage[String, String] ("kafka-spark-test", "testInfo")
producer.send (date)

完整代码

import java.util.Properties
import kafka.javaapi.producer.Producer
import kafka.producer.KeyedMessage
import kafka.producer.ProducerConfig object kafka_producer {
def main(args: Array[String]) {
val props = new Properties()
props.put("metadata.broker.list", "broker1:9092,broker2:9092,broker3:9092")
props.put("serializer.class", "kafka.serializer.StringEncoder")
props.put("request.required.acks", "1") val config = new ProducerConfig(props); val producer = new Producer[String, String](config) val date = new KeyedMessage[String, String]("kafka-spark-test", "testInfo") producer.send(date) producer.close }
}

Tip

如果运行时发现如下错误:

log4j:WARN No appenders could be found for logger (kafka.utils.VerifiableProperties).
log4j:WARN Please initialize the log4j system properly.

log4j.properties加入到src下