Subversion Repositories SmartDukaan

/*

 * Copyright (C) 2011 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.android.volley.mock;

import com.android.volley.NetworkResponse;

import com.android.volley.Request;

import com.android.volley.Response;

import java.util.concurrent.PriorityBlockingQueue;

import java.util.concurrent.Semaphore;

import java.util.concurrent.TimeUnit;

import java.util.concurrent.TimeoutException;

// TODO: the name of this class sucks

@SuppressWarnings("serial")

public class WaitableQueue extends PriorityBlockingQueue<Request<?>> {

    private final Request<?> mStopRequest = new MagicStopRequest();

    private final Semaphore mStopEvent = new Semaphore(0);

    // TODO: this isn't really "until empty" it's "until next call to take() after empty"

    public void waitUntilEmpty(long timeoutMillis)

            throws TimeoutException, InterruptedException {

        add(mStopRequest);

        if (!mStopEvent.tryAcquire(timeoutMillis, TimeUnit.MILLISECONDS)) {

            throw new TimeoutException();

        }

    }

    @Override

    public Request<?> take() throws InterruptedException {

        Request<?> item = super.take();

        if (item == mStopRequest) {

            mStopEvent.release();

            return take();

        }

        return item;

    }

    private static class MagicStopRequest extends Request<Object> {

        public MagicStopRequest() {

            super(Request.Method.GET, "", null);

        }

        @Override

        public Priority getPriority() {

            return Priority.LOW;

        }

        @Override

        protected Response<Object> parseNetworkResponse(NetworkResponse response) {

            return null;

        }

        @Override

        protected void deliverResponse(Object response) {

        }

    }

}