1/*
2 * Copyright (C) 2011 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.volley.mock;
18
19import com.android.volley.NetworkResponse;
20import com.android.volley.Request;
21import com.android.volley.Response;
22
23import java.util.concurrent.PriorityBlockingQueue;
24import java.util.concurrent.Semaphore;
25import java.util.concurrent.TimeUnit;
26import java.util.concurrent.TimeoutException;
27
28// TODO: the name of this class sucks
29@SuppressWarnings({ "serial", "rawtypes" })
30public class WaitableQueue extends PriorityBlockingQueue<Request> {
31    private final Request<?> mStopRequest = new MagicStopRequest();
32    private final Semaphore mStopEvent = new Semaphore(0);
33
34    // TODO: this isn't really "until empty" it's "until next call to take() after empty"
35    public void waitUntilEmpty(long timeoutMillis)
36            throws TimeoutException, InterruptedException {
37        add(mStopRequest);
38        if (!mStopEvent.tryAcquire(timeoutMillis, TimeUnit.MILLISECONDS)) {
39            throw new TimeoutException();
40        }
41    }
42
43    @Override
44    public Request<?> take() throws InterruptedException {
45        Request<?> item = super.take();
46        if (item == mStopRequest) {
47            mStopEvent.release();
48            return take();
49        }
50        return item;
51    }
52
53    private static class MagicStopRequest extends Request<Object> {
54        public MagicStopRequest() {
55            super("", null);
56        }
57
58        @Override
59        public Priority getPriority() {
60            return Priority.LOW;
61        }
62
63        @Override
64        protected Response<Object> parseNetworkResponse(NetworkResponse response) {
65            return null;
66        }
67
68        @Override
69        protected void deliverResponse(Object response) {
70        }
71    }
72}
73