Reimplement the "SkipLast" operator with time

Author: zsxwing

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

@@ -117,6 +117,7 @@
 import rx.operators.OperatorSerialize;
 import rx.operators.OperatorSkip;
 import rx.operators.OperatorSkipLast;
+import rx.operators.OperatorSkipLastTimed;
 import rx.operators.OperatorSkipWhile;
 import rx.operators.OperatorSubscribeOn;
 import rx.operators.OperatorSynchronize;
@@ -6083,7 +6084,7 @@ public final Observable<T> skipLast(long time, TimeUnit unit) {
      * @see <a href="http://msdn.microsoft.com/en-us/library/hh211750.aspx">MSDN: Observable.SkipLast</a>
      */
     public final Observable<T> skipLast(long time, TimeUnit unit, Scheduler scheduler) {
-        return create(new OperatorSkipLast.SkipLastTimed<T>(this, time, unit, scheduler));
+        return lift(new OperatorSkipLastTimed<T>(time, unit, scheduler));
     }
 
     /**

rxjava-core/src/main/java/rx/operators/OperatorSkipLast.java

@@ -15,21 +15,11 @@
  */
 package rx.operators;
 
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.Deque;
 import java.util.LinkedList;
-import java.util.List;
-import java.util.concurrent.TimeUnit;
 
-import rx.Observable;
-import rx.Observable.OnSubscribeFunc;
 import rx.Observable.Operator;
-import rx.Observer;
-import rx.Scheduler;
 import rx.Subscriber;
-import rx.Subscription;
-import rx.schedulers.Timestamped;
 
 /**
  * Bypasses a specified number of elements at the end of an observable sequence.
@@ -85,75 +75,4 @@ public void onNext(T value) {
         };
     }
 
-    /**
-     * Skip delivering values in the time window before the values.
-     *
-     * @param <T>
-     *            the result value type
-     */
-    public static final class SkipLastTimed<T> implements OnSubscribeFunc<T> {
-        final Observable<? extends T> source;
-        final long timeInMillis;
-        final Scheduler scheduler;
-
-        public SkipLastTimed(Observable<? extends T> source, long time, TimeUnit unit, Scheduler scheduler) {
-            this.source = source;
-            this.timeInMillis = unit.toMillis(time);
-            this.scheduler = scheduler;
-        }
-
-        @Override
-        public Subscription onSubscribe(Observer<? super T> t1) {
-            return source.unsafeSubscribe(new SourceObserver<T>(t1, timeInMillis, scheduler));
-        }
-
-        /** Observes the source. */
-        private static final class SourceObserver<T> extends Subscriber<T> {
-            final Observer<? super T> observer;
-            final long timeInMillis;
-            final Scheduler scheduler;
-            List<Timestamped<T>> buffer = new ArrayList<Timestamped<T>>();
-
-            public SourceObserver(Observer<? super T> observer,
-                    long timeInMillis, Scheduler scheduler) {
-                this.observer = observer;
-                this.timeInMillis = timeInMillis;
-                this.scheduler = scheduler;
-            }
-
-            @Override
-            public void onNext(T args) {
-                buffer.add(new Timestamped<T>(scheduler.now(), args));
-            }
-
-            @Override
-            public void onError(Throwable e) {
-                buffer = Collections.emptyList();
-                observer.onError(e);
-            }
-
-            @Override
-            public void onCompleted() {
-                long limit = scheduler.now() - timeInMillis;
-                try {
-                    for (Timestamped<T> v : buffer) {
-                        if (v.getTimestampMillis() < limit) {
-                            try {
-                                observer.onNext(v.getValue());
-                            } catch (Throwable t) {
-                                observer.onError(t);
-                                return;
-                            }
-                        } else {
-                            observer.onCompleted();
-                            break;
-                        }
-                    }
-                } finally {
-                    buffer = Collections.emptyList();
-                }
-            }
-
-        }
-    }
 }

rxjava-core/src/main/java/rx/operators/OperatorSkipLastTimed.java

@@ -0,0 +1,82 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package rx.operators;
+
+import rx.Observable.Operator;
+import rx.Scheduler;
+import rx.Subscriber;
+import rx.schedulers.Timestamped;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Skip delivering values in the time window before the values.
+ */
+public class OperatorSkipLastTimed<T> implements Operator<T, T> {
+
+    private final long timeInMillis;
+    private final Scheduler scheduler;
+
+    public OperatorSkipLastTimed(long time, TimeUnit unit, Scheduler scheduler) {
+        this.timeInMillis = unit.toMillis(time);
+        this.scheduler = scheduler;
+    }
+
+    @Override
+    public Subscriber<? super T> call(final Subscriber<? super T> subscriber) {
+        return new Subscriber<T>(subscriber) {
+
+            private List<Timestamped<T>> buffer = new ArrayList<Timestamped<T>>();
+
+            @Override
+            public void onNext(T value) {
+                buffer.add(new Timestamped<T>(scheduler.now(), value));
+            }
+
+            @Override
+            public void onError(Throwable e) {
+                buffer = Collections.emptyList();
+                subscriber.onError(e);
+            }
+
+            @Override
+            public void onCompleted() {
+                long limit = scheduler.now() - timeInMillis;
+                try {
+                    for (Timestamped<T> v : buffer) {
+                        if (v.getTimestampMillis() < limit) {
+                            try {
+                                subscriber.onNext(v.getValue());
+                            } catch (Throwable t) {
+                                subscriber.onError(t);
+                                return;
+                            }
+                        } else {
+                            break;
+                        }
+                    }
+                    subscriber.onCompleted();
+                } finally {
+                    buffer = Collections.emptyList();
+                }
+            }
+
+        };
+    }
+}

rxjava-core/src/test/java/rx/operators/OperatorSkipLastTest.java

@@ -23,16 +23,12 @@
 import static org.mockito.Mockito.verify;
 
 import java.util.Arrays;
-import java.util.concurrent.TimeUnit;
 
 import org.junit.Test;
 import org.mockito.InOrder;
 
 import rx.Observable;
 import rx.Observer;
-import rx.operators.OperationSkipTest.CustomException;
-import rx.schedulers.TestScheduler;
-import rx.subjects.PublishSubject;
 
 public class OperatorSkipLastTest {
 
@@ -108,94 +104,4 @@ public void testSkipLastWithNegativeCount() {
         Observable.from("one").skipLast(-1);
     }
 
-    @Test
-    public void testSkipLastTimed() {
-        TestScheduler scheduler = new TestScheduler();
-
-        PublishSubject<Integer> source = PublishSubject.create();
-
-        Observable<Integer> result = source.skipLast(1, TimeUnit.SECONDS, scheduler);
-
-        Observer<Object> o = mock(Observer.class);
-
-        result.subscribe(o);
-
-        source.onNext(1);
-        source.onNext(2);
-        source.onNext(3);
-
-        scheduler.advanceTimeBy(500, TimeUnit.MILLISECONDS);
-
-        source.onNext(4);
-        source.onNext(5);
-        source.onNext(6);
-
-        scheduler.advanceTimeBy(950, TimeUnit.MILLISECONDS);
-        source.onCompleted();
-
-        InOrder inOrder = inOrder(o);
-        inOrder.verify(o).onNext(1);
-        inOrder.verify(o).onNext(2);
-        inOrder.verify(o).onNext(3);
-        inOrder.verify(o, never()).onNext(4);
-        inOrder.verify(o, never()).onNext(5);
-        inOrder.verify(o, never()).onNext(6);
-        inOrder.verify(o).onCompleted();
-        inOrder.verifyNoMoreInteractions();
-
-        verify(o, never()).onError(any(Throwable.class));
-    }
-
-    @Test
-    public void testSkipLastTimedErrorBeforeTime() {
-        TestScheduler scheduler = new TestScheduler();
-
-        PublishSubject<Integer> source = PublishSubject.create();
-
-        Observable<Integer> result = source.skipLast(1, TimeUnit.SECONDS, scheduler);
-
-        Observer<Object> o = mock(Observer.class);
-
-        result.subscribe(o);
-
-        source.onNext(1);
-        source.onNext(2);
-        source.onNext(3);
-        source.onError(new OperationSkipTest.CustomException());
-
-        scheduler.advanceTimeBy(1050, TimeUnit.MILLISECONDS);
-
-        verify(o).onError(any(CustomException.class));
-
-        verify(o, never()).onCompleted();
-        verify(o, never()).onNext(any());
-    }
-
-    @Test
-    public void testSkipLastTimedCompleteBeforeTime() {
-        TestScheduler scheduler = new TestScheduler();
-
-        PublishSubject<Integer> source = PublishSubject.create();
-
-        Observable<Integer> result = source.skipLast(1, TimeUnit.SECONDS, scheduler);
-
-        Observer<Object> o = mock(Observer.class);
-
-        result.subscribe(o);
-
-        source.onNext(1);
-        source.onNext(2);
-        source.onNext(3);
-
-        scheduler.advanceTimeBy(500, TimeUnit.MILLISECONDS);
-
-        source.onCompleted();
-
-        InOrder inOrder = inOrder(o);
-        inOrder.verify(o).onCompleted();
-        inOrder.verifyNoMoreInteractions();
-
-        verify(o, never()).onNext(any());
-        verify(o, never()).onError(any(Throwable.class));
-    }
 }