scala> def currentMethodName() : String = Thread.currentThread.getStackTrace()(2).getMethodName currentMethodName: ()String scala> def getMeASammy() = { println(currentMethodName()) } getMeASammy: ()Unit scala> getMeASammy() getMeASammy
In IntelliJ 2016.x you upgrade Scala by Ensure Scala Plugin up to date. Then by going to: File | Other Settings | Default Project Structure | Global Libraries Click the + button at the top left hand side of the Window Select Scala SDK Choose the version you want to install.
Just to post as an answer – the SparkContext can be accessed from SparkSession using spark.sparkContext (no parenthesis)
Pattern matching def aMethod(param: String = null) { val paramOrDefault = param match { case null => “asdf” case s => s } } Option (implicitly) def aMethod(param: String = null) { val paramOrDefault = Option(param).getOrElse(“asdf”) } Option (explicitly) def aMethod(param: Option[String] = None) { val paramOrDefault = param getOrElse “asdf” } The last approach … Read more
Take a look at this example, I will define a function printme that takes vargs of type String def printme(s: String*) = s.foreach(println) scala> printme(List(“a”,”b”,”c”)) <console>:9: error: type mismatch; found : List[String] required: String printme(List(a,b,c)) What you really need to un-pack the list into arguments with the :_* operator scala> val mylist = List(“1″,”2″,”3”) scala> … Read more
Yes, it’s called scala-java8-compat, and here’s the method you’re looking for.
Firstly, some meta-advice. Any time you’re wondering how the compiler expands some syntactic sugar, infers a type, or applies an implicit conversion, use scala -Xprint:typer -e <expr> to show you what happened. scala -Xprint:typer -e “val a = 2; ~a” … private[this] val a: Int = 2; private <stable> <accessor> def a: Int = $anon.this.a; … Read more
This is a fundamental feature of object-oriented programming that doesn’t get as much attention as it deserves. Suppose you have a collection C[+T]. What the +T means is that if U <: T, then C[U] <: C[T]. Fair enough. But what does it mean to be a subclass? It means that every method should work … Read more
The problem is when using sbt:assembly the default merge strategy excludes all the reference.conf files as per If multiple files share the same relative path (e.g. a resource named application.conf in multiple dependency JARs), the default strategy is to verify that all candidates have the same contents and error out otherwise. The solution is to … Read more
All of the option parameters are passed in the option() function as below: val segments = sqlContext.read.format(“com.databricks.spark.csv”) .option(“delimiter”, “\t”) .load(“s3n://michaeldiscenza/data/test_segments”)