1/*
2 * Copyright (C) 2013 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#ifndef ANDROID_HWUI_FUTURE_H
18#define ANDROID_HWUI_FUTURE_H
19
20#include <utils/RefBase.h>
21
22#include "Barrier.h"
23
24namespace android {
25namespace uirenderer {
26
27template<typename T>
28class Future: public LightRefBase<Future<T> > {
29public:
30    Future(Condition::WakeUpType type = Condition::WAKE_UP_ONE): mBarrier(type), mResult() { }
31    ~Future() { }
32
33    /**
34     * Returns the result of this future, blocking if
35     * the result is not available yet.
36     */
37    T get() const {
38        mBarrier.wait();
39        return mResult;
40    }
41
42    /**
43     * This method must be called only once.
44     */
45    void produce(T result) {
46        mResult = result;
47        mBarrier.open();
48    }
49
50private:
51    Barrier mBarrier;
52    T mResult;
53};
54
55}; // namespace uirenderer
56}; // namespace android
57
58#endif // ANDROID_HWUI_FUTURE_H
59