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    explicit Future(Condition::WakeUpType type = Condition::WAKE_UP_ONE)
31            : mBarrier(type), mResult() {}
32    ~Future() {}
33
34    /**
35     * Returns the result of this future, blocking if
36     * the result is not available yet.
37     */
38    T get() const {
39        mBarrier.wait();
40        return mResult;
41    }
42
43    /**
44     * This method must be called only once.
45     */
46    void produce(T result) {
47        mResult = result;
48        mBarrier.open();
49    }
50
51private:
52    Barrier mBarrier;
53    T mResult;
54};
55
56};  // namespace uirenderer
57};  // namespace android
58
59#endif  // ANDROID_HWUI_FUTURE_H
60