1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.camera.async;
18 
19 import com.android.camera.util.Callback;
20 
21 import java.util.concurrent.Executor;
22 
23 import javax.annotation.CheckReturnValue;
24 import javax.annotation.Nonnull;
25 import javax.annotation.ParametersAreNonnullByDefault;
26 
27 @ParametersAreNonnullByDefault
28 public abstract class ForwardingObservable<T> implements Observable<T> {
29     private final Observable<T> mDelegate;
30 
ForwardingObservable(Observable<T> delegate)31     public ForwardingObservable(Observable<T> delegate) {
32         mDelegate = delegate;
33     }
34 
35     @Nonnull
36     @Override
37     @CheckReturnValue
addCallback(Runnable callback, Executor executor)38     public SafeCloseable addCallback(Runnable callback, Executor executor) {
39         return mDelegate.addCallback(callback, executor);
40     }
41 
42     @Nonnull
43     @Override
get()44     public T get() {
45         return mDelegate.get();
46     }
47 }
48