Merge pull request #151 from zsxwing/rxjava-1.0.8

Update to Rxjava 1.0.8 & add onBackpressureDropDo to ExperimentalAPIs

Author: zsxwing

README.md

@@ -81,6 +81,7 @@ Since RxScala is part of the RxJava family the communication channels are simila
 
 | RxScala version | Compatible RxJava version |
 | ------------------- | ------------------------- |
+| 0.24.* | 1.0.* |
 | 0.23.*<sup>[1]</sup> | 1.0.* |
 | 0.22.0 | 1.0.0-rc.5 |
 | 0.21.1 | 1.0.0-rc.3 |
@@ -89,12 +90,13 @@ Since RxScala is part of the RxJava family the communication channels are simila
 [1] You can use any release of RxScala 0.23 with any release of RxJava 1.0. E.g, use RxScala 0.23.0 with RxJava 1.0.1 <br/>
 [2] You should use the same version of RxScala with RxJava. E.g, use RxScala 0.20.1 with RxJava 0.20.1
 
-From 0.23.2, RxScala adds ExperimentalAPIs, which contains APIs using RxJava Beta/Experimental APIs. As these APIs are unstable in RxJava,
+From 0.24.0, RxScala adds ExperimentalAPIs, which contains APIs using RxJava Beta/Experimental APIs. As these APIs are unstable in RxJava,
 if you `import ExperimentalAPIs`, you should use the corresponding version of RxJava as the following table:
 
 | RxScala version | Compatible RxJava version |
 | ------------------- | ------------------------- |
-| 0.23.2 | 1.0.7 |
+| 0.24.1 | 1.0.8+ |
+| 0.24.0 | 1.0.7+ |
 
 ## Full Documentation
 

build.sbt

@@ -17,7 +17,7 @@ scalaVersion in ThisBuild := "2.11.2"
 crossScalaVersions in ThisBuild := Seq("2.10.4", "2.11.2")
 
 libraryDependencies ++= Seq(
-  "io.reactivex" % "rxjava" % "1.0.7",
+  "io.reactivex" % "rxjava" % "1.0.8",
   "org.mockito" % "mockito-core" % "1.9.5" % "test",
   "junit" % "junit" % "4.11" % "test",
   "org.scalatest" %% "scalatest" % "2.2.2" % "test")

examples/src/test/scala/rx/lang/scala/examples/ExperimentalAPIExamples.scala

@@ -143,4 +143,16 @@ object ExperimentalAPIExamples {
         10)
       .toBlocking.foreach(v => System.out.println("Received: " + v))
   }
+
+  @Test def onBackpressureDropDoExample(): Unit = {
+    Observable[Int](subscriber => {
+      (1 to 200).foreach(subscriber.onNext)
+    }).onBackpressureDropDo {
+      t => println(s"Dropping $t")
+    }.observeOn(IOScheduler()).subscribe {
+      v =>
+        Thread.sleep(10) // A slow consumer
+        println(s"process $v")
+    }
+  }
 }

src/main/scala/rx/lang/scala/ExperimentalAPIs.scala

@@ -241,6 +241,27 @@ class ExperimentalObservable[+T](private val o: Observable[T]) {
     }
     toScalaObservable[R](o.asJavaObservable.flatMap[R](jOnNext, jOnError, jOnCompleted, maxConcurrent))
   }
+
+  /**
+   * Instructs an [[Observable]] that is emitting items faster than its observer can consume them to discard,
+   * rather than emit, those items that its observer is not prepared to observe.
+   *
+   * <img width="640" height="245" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.drop.png" alt="">
+   *
+   * If the downstream request count hits `0` then the [[Observable]] will refrain from calling `onNext` until
+   * the observer invokes `request(n)` again to increase the request count.
+   *
+   * $noDefaultScheduler
+   *
+   * @param onDrop the action to invoke for each item dropped. `onDrop` action should be fast and should never block.
+   * @return an new [[Observable]] that will drop `onNext` notifications on overflow
+   * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a>
+   */
+  def onBackpressureDropDo(onDrop: T => Unit): Observable[T] = {
+    toScalaObservable[T](o.asJavaObservable.onBackpressureDrop(new Action1[T] {
+      override def call(t: T) = onDrop(t)
+    }))
+  }
 }
 
 object ExperimentalAPIs {

src/test/scala/rx/lang/scala/CompletenessTest.scala

@@ -61,6 +61,7 @@ class CompletenessTest extends JUnitSuite {
     "onBackpressureBlock(Int)",
     "onBackpressureBuffer(Long)",
     "onBackpressureBuffer(Long, Action0)",
+    "onBackpressureDrop(Action1[_ >: T])",
     "takeUntil(Func1[_ >: T, Boolean])",
     "using(Func0[Resource], Func1[_ >: Resource, _ <: Observable[_ <: T]], Action1[_ >: Resource], Boolean)",
     "withLatestFrom(Observable[_ <: U], Func2[_ >: T, _ >: U, _ <: R])",