start groupBy examples

Author: samuelgruetter

language-adaptors/rxjava-scala/src/main/scala/rx/lang/scala/examples/Olympics.scala

@@ -0,0 +1,39 @@
+package rx.lang.scala.examples
+
+object Olympics {
+  case class Medal(val year: Int, val games: String, val discipline: String, val medal: String, val athlete: String, val country: String)
+  
+  val mountainBikeMedals = List(
+    Medal(2012, "London 2012", "cross-country men", "Gold", "Jaroslav KULHAVY", "Czech Republic"),
+    Medal(2012, "London 2012", "cross-country men", "Silver", "Nino SCHURTER", "Switzerland"),
+    Medal(2012, "London 2012", "cross-country men", "Bronze", "Marco Aurelio FONTANA", "Italy"),
+    Medal(2012, "London 2012", "cross-country women", "Gold", "Julie BRESSET", "France"),
+    Medal(2012, "London 2012", "cross-country women", "Silver", "Sabine SPITZ", "Germany"),
+    Medal(2012, "London 2012", "cross-country women", "Bronze", "Georgia GOULD", "United States of America"),
+    Medal(2008, "Beijing 2008", "cross-country women", "Gold", "Sabine SPITZ", "Germany"),
+    Medal(2008, "Beijing 2008", "cross-country women", "Silver", "Maja WLOSZCZOWSKA", "Poland"),
+    Medal(2008, "Beijing 2008", "cross-country women", "Bronze", "Irina KALENTYEVA", "Russian Federation"),
+    Medal(2008, "Beijing 2008", "cross-country men", "Gold", "Julien ABSALON", "France"),
+    Medal(2008, "Beijing 2008", "cross-country men", "Silver", "Jean-Christophe PERAUD", "France"),
+    Medal(2008, "Beijing 2008", "cross-country men", "Bronze", "Nino SCHURTER", "Switzerland"),
+    Medal(2004, "Athens 2004", "cross-country men", "Gold", "Julien ABSALON", "France"),
+    Medal(2004, "Athens 2004", "cross-country men", "Silver", "Jose Antonio HERMIDA RAMOS", "Spain"),
+    Medal(2004, "Athens 2004", "cross-country men", "Bronze", "Bart BRENTJENS", "Netherlands"),
+    Medal(2004, "Athens 2004", "cross-country women", "Gold", "Gunn-Rita DAHLE", "Norway"),
+    Medal(2004, "Athens 2004", "cross-country women", "Silver", "Marie-Helene PREMONT", "Canada"),
+    Medal(2004, "Athens 2004", "cross-country women", "Bronze", "Sabine SPITZ", "Germany"),
+    Medal(2000, "Sydney 2000", "cross-country women", "Gold", "Paola PEZZO", "Italy"),
+    Medal(2000, "Sydney 2000", "cross-country women", "Silver", "Barbara BLATTER", "Switzerland"),
+    Medal(2000, "Sydney 2000", "cross-country women", "Bronze", "Marga FULLANA", "Spain"),
+    Medal(2000, "Sydney 2000", "cross-country men", "Gold", "Miguel MARTINEZ", "France"),
+    Medal(2000, "Sydney 2000", "cross-country men", "Silver", "Filip MEIRHAEGHE", "Belgium"),
+    Medal(2000, "Sydney 2000", "cross-country men", "Bronze", "Christoph SAUSER", "Switzerland"),
+    Medal(1996, "Atlanta 1996", "cross-country men", "Silver", "Thomas FRISCHKNECHT", "Switzerland"),
+    Medal(1996, "Atlanta 1996", "cross-country men", "Bronze", "Miguel MARTINEZ", "France"),
+    Medal(1996, "Atlanta 1996", "cross-country men", "Gold", "Bart BRENTJENS", "Netherlands"),
+    Medal(1996, "Atlanta 1996", "cross-country women", "Gold", "Paola PEZZO", "Italy"),
+    Medal(1996, "Atlanta 1996", "cross-country women", "Silver", "Alison SYDOR", "Canada"),
+    Medal(1996, "Atlanta 1996", "cross-country women", "Bronze", "Susan DEMATTEI", "United States of America")
+  ).reverse
+  
+}

language-adaptors/rxjava-scala/src/main/scala/rx/lang/scala/examples/RxScalaDemo.scala

@@ -23,7 +23,7 @@ import org.junit.{Before, Test, Ignore}
 import org.junit.Assert._
 import rx.lang.scala.concurrency.NewThreadScheduler
 
-@Ignore // Since this doesn't do automatic testing, don't increase build time unnecessarily
+//@Ignore // Since this doesn't do automatic testing, don't increase build time unnecessarily
 class RxScalaDemo extends JUnitSuite {
 
   @Test def intervalExample() {
@@ -158,6 +158,49 @@ class RxScalaDemo extends JUnitSuite {
     waitFor(o)
   }
 
+  def sampleAllUntilComplete[T](o: Observable[T], period: Duration): Observable[T] = {
+    for ((element, tick) <- o zip Observable.interval(period)) yield element
+  }
+  
+  @Ignore //TODO
+  @Test def groupByExample() {
+    import Olympics._
+    // `: _*` converts list to varargs
+    val medals = Observable[Medal](Olympics.mountainBikeMedals : _*)
+    
+    // 1 second = 4 years :D
+    val medalsByYear = sampleAllUntilComplete(medals.groupBy(_.year), 1 seconds)
+    
+    /*
+    val t = (for ((year, medals) <- medalsByYear) yield medals).flatMap(ms => ms)
+    t.subscribe(println(_))
+    */
+    
+    val timedMedals = for ((year, medals) <- medalsByYear; medal <- medals) yield medal 
+    
+    timedMedals.subscribe(println(_)) // doesn't print ???
+    
+    Thread.sleep(5000)
+    
+    /*
+    medalsByYear.subscribe(p => println(p._1))
+    
+    //waitFor(medalsByYear)
+    
+    val byCountry = medals.groupBy(_.country)
+    
+    def score(medals: Observable[Medal]) = medals.fold((0, 0, 0))((s, m) => (s, m.medal) match {
+      case ((gold, silver, bronze), "Gold") => (gold+1, silver, bronze)
+      case ((gold, silver, bronze), "Silver") => (gold, silver+1, bronze)
+      case ((gold, silver, bronze), "Bronze") => (gold, silver, bronze+1)
+    })    
+    
+    val scores = for ((country, medals) <- byCountry) yield (country, score(medals))
+    
+    println(scores.toBlockingObservable.toList)
+    */
+  }
+  
   def output(s: String): Unit = println(s)
 
   // blocks until obs has completed