OperatorToObservableFuture

Author: zsxwing

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

@@ -86,7 +86,6 @@
 import rx.operators.OperationTimer;
 import rx.operators.OperationToMap;
 import rx.operators.OperationToMultimap;
-import rx.operators.OperationToObservableFuture;
 import rx.operators.OperationUsing;
 import rx.operators.OperationWindow;
 import rx.operators.OperatorAll;
@@ -121,6 +120,7 @@
 import rx.operators.OperatorTimeout;
 import rx.operators.OperatorTimeoutWithSelector;
 import rx.operators.OperatorTimestamp;
+import rx.operators.OperatorToObservableFuture;
 import rx.operators.OperatorToObservableList;
 import rx.operators.OperatorToObservableSortedList;
 import rx.operators.OperatorUnsubscribeOn;
@@ -1083,7 +1083,7 @@ public final static <T> Observable<T> error(Throwable exception, Scheduler sched
      * @see <a href="https://github.com/Netflix/RxJava/wiki/Creating-Observables#wiki-from">RxJava Wiki: from()</a>
      */
     public final static <T> Observable<T> from(Future<? extends T> future) {
-        return create(OperationToObservableFuture.toObservableFuture(future));
+        return create(OperatorToObservableFuture.toObservableFuture(future));
     }
 
     /**
@@ -1109,7 +1109,7 @@ public final static <T> Observable<T> from(Future<? extends T> future) {
      * @see <a href="https://github.com/Netflix/RxJava/wiki/Creating-Observables#wiki-from">RxJava Wiki: from()</a>
      */
     public final static <T> Observable<T> from(Future<? extends T> future, long timeout, TimeUnit unit) {
-        return create(OperationToObservableFuture.toObservableFuture(future, timeout, unit));
+        return create(OperatorToObservableFuture.toObservableFuture(future, timeout, unit));
     }
 
     /**
@@ -1132,7 +1132,7 @@ public final static <T> Observable<T> from(Future<? extends T> future, long time
      * @see <a href="https://github.com/Netflix/RxJava/wiki/Creating-Observables#wiki-from">RxJava Wiki: from()</a>
      */
     public final static <T> Observable<T> from(Future<? extends T> future, Scheduler scheduler) {
-        return create(OperationToObservableFuture.toObservableFuture(future)).subscribeOn(scheduler);
+        return create(OperatorToObservableFuture.toObservableFuture(future)).subscribeOn(scheduler);
     }
 
     /**

rxjava-core/src/main/java/rx/operators/OperationToObservableFuture.java renamed to rxjava-core/src/main/java/rx/operators/OperatorToObservableFuture.java

@@ -18,9 +18,9 @@
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 
-import rx.Observable.OnSubscribeFunc;
-import rx.Observer;
-import rx.Subscription;
+import rx.Observable.OnSubscribe;
+import rx.Subscriber;
+import rx.functions.Action0;
 import rx.subscriptions.Subscriptions;
 
 /**
@@ -34,15 +34,15 @@
  * This is blocking so the Subscription returned when calling
  * <code>Observable.unsafeSubscribe(Observer)</code> does nothing.
  */
-public class OperationToObservableFuture {
-    /* package accessible for unit tests */static class ToObservableFuture<T> implements OnSubscribeFunc<T> {
+public class OperatorToObservableFuture {
+    /* package accessible for unit tests */static class ToObservableFuture<T> implements OnSubscribe<T> {
         private final Future<? extends T> that;
-        private final Long time;
+        private final long time;
         private final TimeUnit unit;
 
         public ToObservableFuture(Future<? extends T> that) {
             this.that = that;
-            this.time = null;
+            this.time = 0;
             this.unit = null;
         }
 
@@ -53,29 +53,34 @@ public ToObservableFuture(Future<? extends T> that, long time, TimeUnit unit) {
         }
 
         @Override
-        public Subscription onSubscribe(Observer<? super T> observer) {
-            try {
-                T value = (time == null) ? (T) that.get() : (T) that.get(time, unit);
-
-                if (!that.isCancelled()) {
-                    observer.onNext(value);
+        public void call(Subscriber<? super T> subscriber) {
+            subscriber.add(Subscriptions.create(new Action0() {
+                @Override
+                public void call() {
+                    // If the Future is already completed, "cancel" does nothing.
+                    that.cancel(true);
                 }
-                observer.onCompleted();
+            }));
+            try {
+                T value = (unit == null) ? (T) that.get() : (T) that.get(time, unit);
+                subscriber.onNext(value);
+                subscriber.onCompleted();
             } catch (Throwable e) {
-                observer.onError(e);
+                // If this Observable is unsubscribed, we will receive an CancellationException.
+                // However, CancellationException will not be passed to the final Subscriber
+                // since it's already subscribed.
+                // If the Future is canceled in other place, CancellationException will be still
+                // passed to the final Subscriber.
+                subscriber.onError(e);
             }
-
-            // the get() has already completed so there is no point in
-            // giving the user a way to cancel.
-            return Subscriptions.empty();
         }
     }
 
-    public static <T> OnSubscribeFunc<T> toObservableFuture(final Future<? extends T> that) {
+    public static <T> OnSubscribe<T> toObservableFuture(final Future<? extends T> that) {
         return new ToObservableFuture<T>(that);
     }
 
-    public static <T> OnSubscribeFunc<T> toObservableFuture(final Future<? extends T> that, long time, TimeUnit unit) {
+    public static <T> OnSubscribe<T> toObservableFuture(final Future<? extends T> that, long time, TimeUnit unit) {
         return new ToObservableFuture<T>(that, time, unit);
     }
 }

rxjava-core/src/test/java/rx/operators/OperationToObservableFutureTest.java renamed to rxjava-core/src/test/java/rx/operators/OperatorToObservableFutureTest.java

@@ -15,6 +15,7 @@
  */
 package rx.operators;
 
+import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.times;
@@ -25,44 +26,42 @@
 
 import org.junit.Test;
 
+import rx.Observable;
 import rx.Observer;
 import rx.Subscription;
 import rx.observers.TestObserver;
-import rx.operators.OperationToObservableFuture.ToObservableFuture;
 
-public class OperationToObservableFutureTest {
+public class OperatorToObservableFutureTest {
 
     @Test
     public void testSuccess() throws Exception {
         Future<Object> future = mock(Future.class);
         Object value = new Object();
         when(future.get()).thenReturn(value);
-        ToObservableFuture<Object> ob = new ToObservableFuture<Object>(future);
         Observer<Object> o = mock(Observer.class);
 
-        Subscription sub = ob.onSubscribe(new TestObserver<Object>(o));
+        Subscription sub = Observable.from(future).subscribe(new TestObserver<Object>(o));
         sub.unsubscribe();
 
         verify(o, times(1)).onNext(value);
         verify(o, times(1)).onCompleted();
-        verify(o, never()).onError(null);
-        verify(future, never()).cancel(true);
+        verify(o, never()).onError(any(Throwable.class));
+        verify(future, times(1)).cancel(true);
     }
 
     @Test
     public void testFailure() throws Exception {
         Future<Object> future = mock(Future.class);
         RuntimeException e = new RuntimeException();
         when(future.get()).thenThrow(e);
-        ToObservableFuture<Object> ob = new ToObservableFuture<Object>(future);
         Observer<Object> o = mock(Observer.class);
 
-        Subscription sub = ob.onSubscribe(new TestObserver<Object>(o));
+        Subscription sub = Observable.from(future).subscribe(new TestObserver<Object>(o));
         sub.unsubscribe();
 
         verify(o, never()).onNext(null);
         verify(o, never()).onCompleted();
         verify(o, times(1)).onError(e);
-        verify(future, never()).cancel(true);
+        verify(future, times(1)).cancel(true);
     }
 }