From 32fa611b19c6b95d4563be631c5a8ff0cdf3438f Mon Sep 17 00:00:00 2001 From: Dice Date: Tue, 19 May 2015 18:12:05 +0100 Subject: [SPARK-7704] Updating Programming Guides per SPARK-4397 The change per SPARK-4397 makes implicit objects in SparkContext to be found by the compiler automatically. So that we don't need to import the o.a.s.SparkContext._ explicitly any more and can remove some statements around the "implicit conversions" from the latest Programming Guides (1.3.0 and higher) Author: Dice Closes #6234 from daisukebe/patch-1 and squashes the following commits: b77ecd9 [Dice] fix a typo 45dfcd3 [Dice] rewording per Sean's advice a094bcf [Dice] Adding a note for users on any previous releases a29be5f [Dice] Updating Programming Guides per SPARK-4397 --- docs/programming-guide.md | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'docs/programming-guide.md') diff --git a/docs/programming-guide.md b/docs/programming-guide.md index 0c273769bb..07a4d29fe7 100644 --- a/docs/programming-guide.md +++ b/docs/programming-guide.md @@ -41,14 +41,15 @@ In addition, if you wish to access an HDFS cluster, you need to add a dependency artifactId = hadoop-client version = -Finally, you need to import some Spark classes and implicit conversions into your program. Add the following lines: +Finally, you need to import some Spark classes into your program. Add the following lines: {% highlight scala %} import org.apache.spark.SparkContext -import org.apache.spark.SparkContext._ import org.apache.spark.SparkConf {% endhighlight %} +(Before Spark 1.3.0, you need to explicitly `import org.apache.spark.SparkContext._` to enable essential implicit conversions.) +
@@ -821,11 +822,9 @@ by a key. In Scala, these operations are automatically available on RDDs containing [Tuple2](http://www.scala-lang.org/api/{{site.SCALA_VERSION}}/index.html#scala.Tuple2) objects -(the built-in tuples in the language, created by simply writing `(a, b)`), as long as you -import `org.apache.spark.SparkContext._` in your program to enable Spark's implicit -conversions. The key-value pair operations are available in the +(the built-in tuples in the language, created by simply writing `(a, b)`). The key-value pair operations are available in the [PairRDDFunctions](api/scala/index.html#org.apache.spark.rdd.PairRDDFunctions) class, -which automatically wraps around an RDD of tuples if you import the conversions. +which automatically wraps around an RDD of tuples. For example, the following code uses the `reduceByKey` operation on key-value pairs to count how many times each line of text occurs in a file: -- cgit v1.2.3