Spark自定义分区器

自定义分区器：创建一个类继承Partitioner，并实现方法

下方代码实现功能：把偶数放到0分区，基数放到1分区

import org.apache.spark.rdd.RDD
import org.apache.spark.{Partitioner, SparkConf, SparkContext, TaskContext}

object TestPartitioner {
    def main(args: Array[String]): Unit = {
        val sc = new SparkContext(new SparkConf().setAppName("TestPartitioner").setMaster("local"))
        //过滤日志
        sc.setLogLevel("error")
        //创建RDD
        val rdd: RDD[String] = sc.textFile("file//day1014TestPartitioner", 5)
        //处理数据
        rdd.flatMap(_.split(" ")).map((_, 1)).partitionBy(new MyPartitioner(2)).foreachPartition(fp => {
            println("分区ID:" + TaskContext.get.partitionId)
            fp.foreach(println)
        })
    }
}

class MyPartitioner(n: Int) extends Partitioner {
    override def numPartitions: Int = n

    override def getPartition(key: Any): Int = {
        if (key.toString.toInt % 2 == 0) {
            0
        } else {
            1
        }
    }
}

1 2 3 4 5 6 7 8 9 10

分区ID:0
(2,1)
(4,1)
(6,1)
(8,1)
(10,1)
分区ID:1
(1,1)
(3,1)
(5,1)
(7,1)
(9,1)