Merge pull request #952 from zsxwing/amb

rxjava-scala improvements and reimplemented the `amb` operator

Author: benjchristensen

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

@@ -533,4 +533,35 @@ class RxScalaDemo extends JUnitSuite {
     println(result)
   }
 
+  @Test def ambExample(): Unit = {
+    val o1 = List(100L, 200L, 300L).toObservable.delay(4 seconds)
+    val o2 = List(1000L, 2000L, 3000L).toObservable.delay(2 seconds)
+    val result = o1.amb(o2).toBlockingObservable.toList
+    println(result)
+  }
+
+  @Test def delayExample(): Unit = {
+    val o = List(100L, 200L, 300L).toObservable.delay(2 seconds)
+    val result = o.toBlockingObservable.toList
+    println(result)
+  }
+
+  @Test def delayExample2(): Unit = {
+    val o = List(100L, 200L, 300L).toObservable.delay(2 seconds, IOScheduler())
+    val result = o.toBlockingObservable.toList
+    println(result)
+  }
+
+  @Test def delaySubscriptionExample(): Unit = {
+    val o = List(100L, 200L, 300L).toObservable.delaySubscription(2 seconds)
+    val result = o.toBlockingObservable.toList
+    println(result)
+  }
+
+  @Test def delaySubscriptionExample2(): Unit = {
+    val o = List(100L, 200L, 300L).toObservable.delaySubscription(2 seconds, IOScheduler())
+    val result = o.toBlockingObservable.toList
+    println(result)
+  }
+
 }

language-adaptors/rxjava-scala/src/main/scala/rx/lang/scala/Observable.scala

@@ -2236,6 +2236,75 @@ trait Observable[+T]
   def doOnEach(onNext: T => Unit, onError: Throwable => Unit, onCompleted: () => Unit): Observable[T] = {
     toScalaObservable[T](asJavaObservable.doOnEach(Observer(onNext, onError,onCompleted)))
   }
+
+  /**
+   * Given two Observables, mirror the one that first emits an item.
+   *
+   * <img width="640" src="https://raw.github.com/wiki/Netflix/RxJava/images/rx-operators/amb.png">
+   *
+   * @param that
+   *            an Observable competing to react first
+   * @return an Observable that emits the same sequence of items as whichever of `this` or `that` first emitted an item.
+   */
+  def amb[U >: T](that: Observable[U]): Observable[U] = {
+    val thisJava: rx.Observable[_ <: U] = this.asJavaObservable
+    val thatJava: rx.Observable[_ <: U] = that.asJavaObservable
+    toScalaObservable[U](rx.Observable.amb(thisJava, thatJava))
+  }
+
+  /**
+   * Returns an Observable that emits the items emitted by the source Observable shifted forward in time by a
+   * specified delay. Error notifications from the source Observable are not delayed.
+   *
+   * <img width="640" src="https://raw.github.com/wiki/Netflix/RxJava/images/rx-operators/delay.png">
+   * 
+   * @param delay the delay to shift the source by
+   * @return the source Observable shifted in time by the specified delay
+   */
+  def delay(delay: Duration): Observable[T] = {
+    toScalaObservable[T](asJavaObservable.delay(delay.length, delay.unit))
+  }
+
+  /**
+   * Returns an Observable that emits the items emitted by the source Observable shifted forward in time by a
+   * specified delay. Error notifications from the source Observable are not delayed.
+   *
+   * <img width="640" src="https://raw.github.com/wiki/Netflix/RxJava/images/rx-operators/delay.s.png">
+   * 
+   * @param delay the delay to shift the source by
+   * @param scheduler the Scheduler to use for delaying
+   * @return the source Observable shifted in time by the specified delay
+   */
+  def delay(delay: Duration, scheduler: Scheduler): Observable[T] = {
+    toScalaObservable[T](asJavaObservable.delay(delay.length, delay.unit, scheduler))
+  }
+
+  /**
+   * Return an Observable that delays the subscription to the source Observable by a given amount of time.
+   *
+   * <img width="640" src="https://raw.github.com/wiki/Netflix/RxJava/images/rx-operators/delaySubscription.png">
+   * 
+   * @param delay the time to delay the subscription
+   * @return an Observable that delays the subscription to the source Observable by the given amount
+   */
+  def delaySubscription(delay: Duration): Observable[T] = {
+    toScalaObservable[T](asJavaObservable.delaySubscription(delay.length, delay.unit))
+  }
+
+  /**
+   * Return an Observable that delays the subscription to the source Observable by a given amount of time,
+   * both waiting and subscribing on a given Scheduler.
+   *
+   * <img width="640" src="https://raw.github.com/wiki/Netflix/RxJava/images/rx-operators/delaySubscription.s.png">
+   * 
+   * @param delay the time to delay the subscription
+   * @param scheduler the Scheduler on which the waiting and subscription will happen
+   * @return an Observable that delays the subscription to the source Observable by a given
+   *         amount, waiting and subscribing on the given Scheduler
+   */
+  def delaySubscription(delay: Duration, scheduler: Scheduler): Observable[T] = {
+    toScalaObservable[T](asJavaObservable.delaySubscription(delay.length, delay.unit, scheduler))
+  }
 }
 
 /**

rxjava-core/src/main/java/rx/Observable.java

@@ -52,7 +52,7 @@
 import rx.operators.OnSubscribeFromIterable;
 import rx.operators.OnSubscribeRange;
 import rx.operators.OperationAll;
-import rx.operators.OperationAmb;
+import rx.operators.OperatorAmb;
 import rx.operators.OperationAny;
 import rx.operators.OperationAsObservable;
 import rx.operators.OperationAverage;
@@ -300,7 +300,7 @@ public void call(Subscriber<? super R> o) {
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229115.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Iterable<? extends Observable<? extends T>> sources) {
-        return create(OperationAmb.amb(sources));
+        return create(OperatorAmb.amb(sources));
     }
 
     /**
@@ -318,7 +318,7 @@ public final static <T> Observable<T> amb(Iterable<? extends Observable<? extend
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2) {
-        return create(OperationAmb.amb(o1, o2));
+        return create(OperatorAmb.amb(o1, o2));
     }
 
     /**
@@ -338,7 +338,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3) {
-        return create(OperationAmb.amb(o1, o2, o3));
+        return create(OperatorAmb.amb(o1, o2, o3));
     }
 
     /**
@@ -360,7 +360,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4) {
-        return create(OperationAmb.amb(o1, o2, o3, o4));
+        return create(OperatorAmb.amb(o1, o2, o3, o4));
     }
 
     /**
@@ -384,7 +384,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5) {
-        return create(OperationAmb.amb(o1, o2, o3, o4, o5));
+        return create(OperatorAmb.amb(o1, o2, o3, o4, o5));
     }
 
     /**
@@ -410,7 +410,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6) {
-        return create(OperationAmb.amb(o1, o2, o3, o4, o5, o6));
+        return create(OperatorAmb.amb(o1, o2, o3, o4, o5, o6));
     }
 
     /**
@@ -438,7 +438,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6, Observable<? extends T> o7) {
-        return create(OperationAmb.amb(o1, o2, o3, o4, o5, o6, o7));
+        return create(OperatorAmb.amb(o1, o2, o3, o4, o5, o6, o7));
     }
 
     /**
@@ -468,7 +468,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6, Observable<? extends T> o7, Observable<? extends T> o8) {
-        return create(OperationAmb.amb(o1, o2, o3, o4, o5, o6, o7, o8));
+        return create(OperatorAmb.amb(o1, o2, o3, o4, o5, o6, o7, o8));
     }
 
     /**
@@ -500,7 +500,7 @@ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh229733.aspx">MSDN: Observable.Amb</a>
      */
     public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6, Observable<? extends T> o7, Observable<? extends T> o8, Observable<? extends T> o9) {
-        return create(OperationAmb.amb(o1, o2, o3, o4, o5, o6, o7, o8, o9));
+        return create(OperatorAmb.amb(o1, o2, o3, o4, o5, o6, o7, o8, o9));
     }
 
     /**