/*
Copyright © 2013-2014, Silent Circle, LLC.
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
    * Any redistribution, use, or modification is done solely for personal 
      benefit and not for any commercial purpose or for monetary gain
    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    * Neither the name Silent Circle nor the names of its contributors may 
      be used to endorse or promote products derived from this software 
      without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL SILENT CIRCLE, LLC BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

/*
 * 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.silentcircle.contacts.utils;

import android.os.AsyncTask;

import java.util.concurrent.Executor;

/**
 * Interface used to submit {@link AsyncTask} objects to run in the background.
 * <p>
 * This interface has a direct parallel with the {@link Executor} interface. It exists to decouple
 * the mechanics of AsyncTask submission from the description of how that AsyncTask will execute.
 * <p>
 * One immediate benefit of this approach is that testing becomes much easier, since it is easy to
 * introduce a mock or fake AsyncTaskExecutor in unit/integration tests, and thus inspect which
 * tasks have been submitted and control their execution in an orderly manner.
 * <p>
 * Another benefit in due course will be the management of the submitted tasks. An extension to this
 * interface is planned to allow Activities to easily cancel all the submitted tasks that are still
 * pending in the onDestroy() method of the Activity.
 */
public interface AsyncTaskExecutor {
    /**
     * Executes the given AsyncTask with the default Executor.
     * <p>
     * This method <b>must only be called from the ui thread</b>.
     * <p>
     * The identifier supplied is any Object that can be used to identify the task later. Most
     * commonly this will be an enum which the tests can also refer to. {@code null} is also
     * accepted, though of course this won't help in identifying the task later.
     */
    <T> AsyncTask<T, ?, ?> submit(Object identifier, AsyncTask<T, ?, ?> task, T... params);
}