/*
 * Copyright 2012 Google Inc. All Rights Reserved.
 * Modified Copyright 2018 Wilco van Beijnum.
 *
 * 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.wilco375.onetwoauthenticate.timesync;

import android.os.Handler;

import java.util.concurrent.Executor;

/**
 * {@link Executor} that invokes {@link Runnable} instances on the thread on which it was created.
 * The assumption is that the thread has a {@link android.os.Looper} associated with it.
 *
 * @author klyubin@google.com (Alex Klyubin)
 */
public class RunOnThisLooperThreadExecutor implements Executor {

    private final Handler mHandler = new Handler();

    @Override
    public void execute(Runnable command) {
        if (Thread.currentThread() == mHandler.getLooper().getThread()) {
            // The calling thread is the target thread of the Handler -- invoke immediately, blocking
            // the calling thread.
            command.run();
        } else {
            // The calling thread is not the same as the thread with which the Handler is associated --
            // post to the Handler for later execution.
            mHandler.post(command);
        }
    }
}
