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
17package com.android.camera.async;
18
19import com.android.camera.util.Callback;
20
21import java.util.concurrent.Executor;
22
23import javax.annotation.ParametersAreNonnullByDefault;
24import javax.annotation.concurrent.ThreadSafe;
25
26/**
27 * Wraps a not-necessarily-thread-safe callback into a thread-safe callback
28 * which runs it on an executor.
29 */
30@ThreadSafe
31@ParametersAreNonnullByDefault
32public class ExecutorCallback<T> implements Updatable<T> {
33    private final Callback<T> mCallback;
34    private final Executor mExecutor;
35
36    /**
37     * @param callback The callback to wrap.
38     * @param executor The executor on which to invoke the callback.
39     */
40    public ExecutorCallback(Callback<T> callback, Executor executor) {
41        mCallback = callback;
42        mExecutor = executor;
43    }
44
45    @Override
46    public void update(final T t) {
47        mExecutor.execute(new Runnable() {
48            @Override
49            public void run() {
50                mCallback.onCallback(t);
51            }
52        });
53    }
54}
55