xref: /aosp_15_r20/development/samples/browseable/MidiScope/src/com.example.android.common.midi/MidiEventThread.java (revision 90c8c64db3049935a07c6143d7fd006e26f8ecca)

/*
 * Copyright (C) 2015 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.example.android.common.midi;

import android.media.midi.MidiSender;
import android.util.Log;

import java.io.IOException;

public class MidiEventThread extends MidiEventScheduler {
    protected static final String TAG = "MidiEventThread";

    private EventThread mEventThread;
    MidiDispatcher mDispatcher = new MidiDispatcher();

    class EventThread extends Thread {
        private boolean go = true;

        @Override
        public void run() {
            while (go) {
                try {
                    MidiEvent event = (MidiEvent) waitNextEvent();
                    try {
                        Log.i(TAG, "Fire event " + event.data[0] + " at "
                                + event.getTimestamp());
                        mDispatcher.send(event.data, 0,
                                event.count, event.getTimestamp());
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                    // Put event back in the pool for future use.
                    addEventToPool(event);
                } catch (InterruptedException e) {
                    // OK, this is how we stop the thread.
                }
            }
        }

        /**
         * Asynchronously tell the thread to stop.
         */
        public void requestStop() {
            go = false;
            interrupt();
        }
    }

    public void start() {
        stop();
        mEventThread = new EventThread();
        mEventThread.start();
    }

    /**
     * Asks the thread to stop then waits for it to stop.
     */
    public void stop() {
        if (mEventThread != null) {
            mEventThread.requestStop();
            try {
                mEventThread.join(500);
            } catch (InterruptedException e) {
                Log.e(TAG,
                        "Interrupted while waiting for MIDI EventScheduler thread to stop.");
            } finally {
                mEventThread = null;
            }
        }
    }

    public MidiSender getSender() {
        return mDispatcher.getSender();
    }

}