这是Java中的示例代码。
public class SparkSample { public static void main(String[] args) { SparkSession spark = SparkSession .builder() .appName("SparkSample") .master("local[*]") .getOrCreate(); //create df List<String> myList = Arrays.asList("one", "two", "three", "four", "five"); Dataset<Row> df = spark.createDataset(myList, Enprers.STRING()).toDF(); df.show(); //using df.as List<String> listOne = df.as(Enprers.STRING()).collectAsList(); System.out.println(listOne); //using df.map List<String> listTwo = df.map(row -> row.mkString(), Enprers.STRING()).collectAsList(); System.out.println(listTwo); }}“ row”是java 8 lambda参数。请检查developer.com/java/start-using-java-lambda-
expressions.html
