第2关:Friend Recommendation - 好友推荐
package net.educoder;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaPairRDD;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import scala.Tuple2;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.List;
public class Step2 {
private static SparkConf conf;
private static JavaSparkContext sc;
static {
conf = new SparkConf().setAppName("step2").setMaster("local");
sc = new JavaSparkContext(conf);
}
/**
*
* @return JavaPairRDD<String, Integer>
*/
public static JavaPairRDD<String, Integer> fun2() {
JavaRDD<String> rdd = sc.textFile("/root/friend.txt");
/**-------------------------------beign-----------------------------------**/
JavaPairRDD<String, Integer> rdd1=rdd.flatMapToPair(line -> {