Initial implementation for interval (ReactiveX#55). Needs a test scheduler...

Author: jmhofer

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

@@ -0,0 +1,83 @@
+/**
+ * Copyright 2013 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 static org.junit.Assert.*;
+import static org.mockito.Matchers.*;
+import static org.mockito.Mockito.*;
+import static rx.operators.Tester.UnitTest.*;
+
+import java.util.concurrent.TimeUnit;
+
+import org.junit.Test;
+
+import rx.Observer;
+import rx.Scheduler;
+import rx.Subscription;
+import rx.concurrency.Schedulers;
+import rx.util.functions.Func0;
+import rx.util.functions.Func1;
+
+/**
+ * Returns an observable sequence that produces a value after each period.
+ * The value starts at 0 and counts up each period.
+ */
+public final class OperationInterval {
+
+    /**
+     * Creates an event each time interval.
+     */
+    public static Func1<Observer<Long>, Subscription> interval(long interval, TimeUnit unit) {
+        return new Interval(interval, unit, Schedulers.currentThread());
+    }
+
+    /**
+     * Creates an event each time interval.
+     */
+    public static Func1<Observer<Long>, Subscription> interval(long interval, TimeUnit unit, Scheduler scheduler) {
+        return new Interval(interval, unit, scheduler);
+    }
+
+    private static class Interval implements Func1<Observer<Long>, Subscription> {
+        private final long interval;
+        private final TimeUnit unit;
+        private final Scheduler scheduler;
+        
+        private long currentValue;
+
+        private Interval(long interval, TimeUnit unit, Scheduler scheduler) {
+            this.interval = interval;
+            this.unit = unit;
+            this.scheduler = scheduler;
+        }
+
+        @Override
+        public Subscription call(final Observer<Long> observer) {
+            return scheduler.schedule(new Func0<Subscription>() {
+                @Override
+                public Subscription call() {
+                    observer.onNext(currentValue);
+                    currentValue++;
+                    return Interval.this.call(observer);
+                }
+            }, interval, unit);
+        }
+    }
+    
+    public static class UnitTest {
+        // TODO
+    }
+}