spark textFile读取多个文件

1.spark textFile读取File

1.1 简单读取文件

val spark = SparkSession.builder()
    .appName("demo")
    .master("local[3]")
    .getOrCreate()

// 读取hdfs文件目录
spark.sparkContext.textFile("/user/data")
spark.sparkContext.textFile("hdfs://10.252.51.58:8088/user/data")
// 读取本地目录
spark.sparkContext.textFile("file://user/data")

1.2 正则模式读取文件

val spark = SparkSession.builder()
    .appName("demo")
    .master("local[3]")
    .getOrCreate()

// 读取hdfs文件目录
spark.sparkContext.textFile("/user/data/201908/0[1-9]/*")

2.spark textFile读取多个File

2.1 将多个文件变成一个 list 作为参数

正确写法：sc.TextFile( filename1 + "," + filename2 + "," + filename3)

val spark = SparkSession.builder()
    .appName("demo")
    .master("local[3]")
    .getOrCreate()

val fileList = Array("/user/data/source1","/user/data/source2","/user/data/source3")
// 读取hdfs文件目录
spark.sparkContext.textFile(fileList.mkString(","))

2.2 使用 union 连接

val spark = SparkSession.builder()
    .appName("demo")
    .master("local[3]")
    .getOrCreate()

val fileList = Array("/user/data/source1","/user/data/source2","/user/data/source3")
//array[RDD]
val fileRDD:Array[RDD[String]] = fileList.map(spark.sparkContext.textFile(_)

spark.sparkContext.union(fileRDD)