1.x: javac 9 compatibility fixes

Author: akarnokd

src/main/java/rx/Observable.java

@@ -609,7 +609,7 @@ public static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? ext
      */
     @SuppressWarnings("unchecked")
     public static <T1, T2, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Func2<? super T1, ? super T2, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -637,7 +637,7 @@ public static <T1, T2, R> Observable<R> combineLatest(Observable<? extends T1> o
      */
     @SuppressWarnings("unchecked")
     public static <T1, T2, T3, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Func3<? super T1, ? super T2, ? super T3, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -668,7 +668,7 @@ public static <T1, T2, T3, R> Observable<R> combineLatest(Observable<? extends T
     @SuppressWarnings("unchecked")
     public static <T1, T2, T3, T4, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4,
             Func4<? super T1, ? super T2, ? super T3, ? super T4, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3, o4), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3, o4), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -701,7 +701,7 @@ public static <T1, T2, T3, T4, R> Observable<R> combineLatest(Observable<? exten
     @SuppressWarnings("unchecked")
     public static <T1, T2, T3, T4, T5, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5,
             Func5<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3, o4, o5), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3, o4, o5), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -736,7 +736,7 @@ public static <T1, T2, T3, T4, T5, R> Observable<R> combineLatest(Observable<? e
     @SuppressWarnings("unchecked")
     public static <T1, T2, T3, T4, T5, T6, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6,
             Func6<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -773,7 +773,7 @@ public static <T1, T2, T3, T4, T5, T6, R> Observable<R> combineLatest(Observable
     @SuppressWarnings("unchecked")
     public static <T1, T2, T3, T4, T5, T6, T7, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7,
             Func7<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -812,7 +812,7 @@ public static <T1, T2, T3, T4, T5, T6, T7, R> Observable<R> combineLatest(Observ
     @SuppressWarnings("unchecked")
     public static <T1, T2, T3, T4, T5, T6, T7, T8, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Observable<? extends T8> o8,
             Func8<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? super T8, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7, o8), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7, o8), Functions.fromFunc(combineFunction));
     }
 
     /**
@@ -854,7 +854,7 @@ public static <T1, T2, T3, T4, T5, T6, T7, T8, R> Observable<R> combineLatest(Ob
     public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Observable<? extends T8> o8,
             Observable<? extends T9> o9,
             Func9<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? super T8, ? super T9, ? extends R> combineFunction) {
-        return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7, o8, o9), Functions.fromFunc(combineFunction));
+        return (Observable<R>)combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7, o8, o9), Functions.fromFunc(combineFunction));
     }
     /**
      * Combines a list of source Observables by emitting an item that aggregates the latest values of each of
@@ -1330,7 +1330,7 @@ public static <T> Observable<T> error(Throwable exception) {
      * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a>
      */
     public static <T> Observable<T> from(Future<? extends T> future) {
-        return create(OnSubscribeToObservableFuture.toObservableFuture(future));
+        return (Observable<T>)create(OnSubscribeToObservableFuture.toObservableFuture(future));
     }
 
     /**
@@ -1361,7 +1361,7 @@ public static <T> Observable<T> from(Future<? extends T> future) {
      * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a>
      */
     public static <T> Observable<T> from(Future<? extends T> future, long timeout, TimeUnit unit) {
-        return create(OnSubscribeToObservableFuture.toObservableFuture(future, timeout, unit));
+        return (Observable<T>)create(OnSubscribeToObservableFuture.toObservableFuture(future, timeout, unit));
     }
 
     /**
@@ -1390,7 +1390,8 @@ public static <T> Observable<T> from(Future<? extends T> future, long timeout, T
      */
     public static <T> Observable<T> from(Future<? extends T> future, Scheduler scheduler) {
         // TODO in a future revision the Scheduler will become important because we'll start polling instead of blocking on the Future
-        return create(OnSubscribeToObservableFuture.toObservableFuture(future)).subscribeOn(scheduler);
+        Observable<T> o = (Observable<T>)create(OnSubscribeToObservableFuture.toObservableFuture(future));
+        return o.subscribeOn(scheduler);
     }
 
     /**
@@ -5834,7 +5835,7 @@ public final <R> Observable<R> flatMapIterable(Func1<? super T, ? extends Iterab
      */
     public final <U, R> Observable<R> flatMapIterable(Func1<? super T, ? extends Iterable<? extends U>> collectionSelector,
             Func2<? super T, ? super U, ? extends R> resultSelector) {
-        return flatMap(OperatorMapPair.convertSelector(collectionSelector), resultSelector);
+        return (Observable<R>)flatMap(OperatorMapPair.convertSelector(collectionSelector), resultSelector);
     }
 
     /**
@@ -5870,7 +5871,7 @@ public final <U, R> Observable<R> flatMapIterable(Func1<? super T, ? extends Ite
     @Beta
     public final <U, R> Observable<R> flatMapIterable(Func1<? super T, ? extends Iterable<? extends U>> collectionSelector,
             Func2<? super T, ? super U, ? extends R> resultSelector, int maxConcurrent) {
-        return flatMap(OperatorMapPair.convertSelector(collectionSelector), resultSelector, maxConcurrent);
+        return (Observable<R>)flatMap(OperatorMapPair.convertSelector(collectionSelector), resultSelector, maxConcurrent);
     }
 
     /**
@@ -6655,7 +6656,7 @@ public final Observable<T> onErrorResumeNext(final Func1<Throwable, ? extends Ob
      * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a>
      */
     public final Observable<T> onErrorResumeNext(final Observable<? extends T> resumeSequence) {
-        return lift(OperatorOnErrorResumeNextViaFunction.withOther(resumeSequence));
+        return lift((Operator<T, T>)OperatorOnErrorResumeNextViaFunction.withOther(resumeSequence));
     }
 
     /**
@@ -6685,7 +6686,7 @@ public final Observable<T> onErrorResumeNext(final Observable<? extends T> resum
      * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a>
      */
     public final Observable<T> onErrorReturn(Func1<Throwable, ? extends T> resumeFunction) {
-        return lift(OperatorOnErrorResumeNextViaFunction.withSingle(resumeFunction));
+        return lift((Operator<T, T>)OperatorOnErrorResumeNextViaFunction.withSingle(resumeFunction));
     }
 
     /**
@@ -6721,7 +6722,7 @@ public final Observable<T> onErrorReturn(Func1<Throwable, ? extends T> resumeFun
      * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a>
      */
     public final Observable<T> onExceptionResumeNext(final Observable<? extends T> resumeSequence) {
-        return lift(OperatorOnErrorResumeNextViaFunction.withException(resumeSequence));
+        return lift((Operator<T, T>)OperatorOnErrorResumeNextViaFunction.withException(resumeSequence));
     }
 
     /**
@@ -10564,7 +10565,7 @@ public final <T2, R> Observable<R> zipWith(Iterable<? extends T2> other, Func2<?
      * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a>
      */
     public final <T2, R> Observable<R> zipWith(Observable<? extends T2> other, Func2<? super T, ? super T2, ? extends R> zipFunction) {
-        return zip(this, other, zipFunction);
+        return (Observable<R>)zip(this, other, zipFunction);
     }
 
     /**