java spark转换算子sortByKey

/**
 * # _*_ coding:utf-8 _*_
 * # Author:xiaoshubiao
 * # Time : 2020/5/14 8:33
 **/
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 org.apache.spark.api.java.function.Function2;
import scala.Tuple2;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class union_test {
    public static void main(String[] args) {
        SparkConf conf = new SparkConf().setMaster("local[*]").setAppName("union_test");
        JavaSparkContext sc = new JavaSparkContext(conf);
        List<String> list = Arrays.asList("a","b","c","d","e");
        JavaRDD<String> parallelize = sc.parallelize(list,2);
        JavaPairRDD<String, Integer> stringIntegerJavaPairRDD = parallelize.mapToPair(x -> new Tuple2<>(x, 1));
        //正序
        stringIntegerJavaPairRDD.sortByKey().collect().forEach(x->System.out.println(x));
        // 倒序
        stringIntegerJavaPairRDD.sortByKey(false).collect().forEach(x->System.out.println(x));

    }
}