Android

// these lines are only in the test app
InputStream inS = getResources ().getAssets ().open ("testmp4.mp4");

int length = inS.available ();
byte[] data = new byte[length];
inS.read (data);
inS.close ();

// in the real world, the other stuff gives me a byte[] array and my code starts here
m_memFile = new MemoryFile (null, length);
m_memFile.writeBytes (data, 0, 0, length);

Method getFD = MemoryFile.class.getMethod ("getFileDescriptor");
m_memFileFD = (FileDescriptor) getFD.invoke (m_memFile);

if (m_player == null)
{
    m_player = new MyPlayer (MainActivity.this.m_events, MainActivity.this.m_memFileFD, MainActivity.this.m_memFile.length (), (SurfaceView) findViewById (R.id.viewerMediaVideo));
}
m_player.play ();

protected MediaExtractor m_extractor  = null;
protected PlayerStates   m_state     = PlayerStates.STOPPED;
private SurfaceHolder    m_surface     = null;
protected FileDescriptor m_memFileFD  = null;
protected long           m_memFileLen = 0;

public MyPlayer (PlayerEvents ev, FileDescriptor fd, long len, SurfaceView s)
{
    m_events = ev;
    m_memFileFD = fd;
    m_memFileLen = len;
    m_surface = s.getHolder ();
}

public void play ()
{
    if (m_state == PlayerStates.STOPPED)
    {
        m_stop = false;
        new Thread (this).start ();
    }
    ...
}

public void run ()
{
    android.os.Process.setThreadPriority (Process.THREAD_PRIORITY_URGENT_AUDIO);

    m_extractor = new MediaExtractor ();
    try
    {
        m_extractor.setDataSource (m_memFileFD, 0, m_memFileLen);
    }
    catch (final Exception excp)
    {
        m_extractor.release ();
        m_extractor = null;

        m_handler.post (new Runnable (){public void run ()
                       {m_events.onError ("can't create extractor: " + excp.getMessage ()); } });
        return;
    }
    ....
}

public class Chat extends AppCompatActivity
{
    LinearLayout layout;
    RelativeLayout layout_2;
    ImageView sendButton;
    EditText messageArea;
    ScrollView scrollView;
    Firebase reference1, reference2;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_chat);

        layout = (LinearLayout) findViewById(R.id.layout1);
        layout_2 = (RelativeLayout)findViewById(R.id.layout2);
        sendButton = (ImageView)findViewById(R.id.sendButton);
        messageArea = (EditText)findViewById(R.id.messageArea);
        scrollView = (ScrollView)findViewById(R.id.scrollView);

        Firebase.setAndroidContext(this);

        reference1 = new Firebase("https://zipa1x.firebaseio.com/messages/" + UserDetails.username + "_" + UserDetails.chatWith);
        reference2 = new Firebase("https://zipa1x.firebaseio.com/messages/" + UserDetails.chatWith + "_" + UserDetails.username);

        sendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String messageText = messageArea.getText().toString();

                if(!messageText.equals("")){
                    Map<String, String> map = new HashMap<String, String>();
                    map.put("message", messageText);
                    map.put("user", UserDetails.username);
                    reference1.push().setValue(map);
                    reference2.push().setValue(map);
                    messageArea.setText("");
                }
            }
        });

        reference1.addChildEventListener(new ChildEventListener()
        {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot, String s) {

                for (DataSnapshot child: dataSnapshot.getChildren())
                {
                    Map map = dataSnapshot.getValue(Map.class);
                    String message = map.get("message").toString();
                    String userName = map.get("user").toString();

                    if (userName.equals(UserDetails.username))
                    {
                        addMessageBox("You:-\n" + message, 1);

                        //sendNotification(message,userName);
                    } else
                    {
                        addMessageBox(UserDetails.chatWith + ":-\n" + message, 2);

                        sendNotification(message,userName);
                    }
                }
            }

            @Override
            public void onChildChanged(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onChildRemoved(DataSnapshot dataSnapshot) {

            }

            @Override
            public void onChildMoved(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onCancelled(FirebaseError firebaseError) {

            }
        });

        scrollView.post(new Runnable() {
            @Override
            public void run() {
                scrollView.fullScroll(View.FOCUS_DOWN);
            }
        });
    }

    public void addMessageBox(String message, int type){
        TextView textView = new TextView(Chat.this);
        textView.setText(message);

        LinearLayout.LayoutParams lp2 = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        lp2.weight = 1.0f;

        if(type == 1) {
            lp2.gravity = Gravity.LEFT;
            textView.setBackgroundResource(R.drawable.bubble_in);
        }
        else{
            lp2.gravity = Gravity.RIGHT;
            textView.setBackgroundResource(R.drawable.bubble_out);
        }
        textView.setLayoutParams(lp2);
        layout.addView(textView);
        //scrollView.fullScroll(View.FOCUS_DOWN);

        scrollView.post(new Runnable() {
            @Override
            public void run() {
                scrollView.fullScroll(View.FOCUS_DOWN);
            }
        });
    }

    private void sendNotification(String message,String userName)
    {
        Intent intent = new Intent(this,Chat.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

        PendingIntent pendingIntent = PendingIntent.getActivity(this,0,intent,PendingIntent.FLAG_ONE_SHOT);

        Uri notificationSound = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

        NotificationManager notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);

        NotificationCompat.Builder builder = (NotificationCompat.Builder) new NotificationCompat.Builder(this)
                .setVisibility(Notification.VISIBILITY_PUBLIC)
                //.setOngoing(true)
                .setSmallIcon(R.mipmap.ic_launcher)
                .setContentTitle(userName)
                .setContentText(message)
                .setSound(notificationSound)
                .setContentIntent(pendingIntent);

        NotificationManager mNotificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        mNotificationManager.notify(0, builder.build());
    }
}