IncrementTimer similar to CountdownTimer in android framework

IncrementTimer.java

public abstract class IncrementTimer {
    /**
     * Millis since epoch when alarm should stop.
     */
    private final long mMillisInFuture;

    /**
     * The interval in millis that the user receives callbacks
     */
    private final long mIncrementInterval;

    private long mMillisPassed;

    /**
     * boolean representing if the timer was cancelled
     */
    private boolean mCancelled = false;

    /**
     * @param millisInFuture    The number of millis in the future from the call
     *                          to {@link #start()} until the increment is done and {@link #onFinish()}
     *                          is called.
     * @param incrementInterval The interval along the way to receive
     *                          {@link #onTick(long)} callbacks.
     */
    public IncrementTimer(long millisInFuture, long incrementInterval) {
        mMillisInFuture = millisInFuture;
        mIncrementInterval = incrementInterval;
    }

    public IncrementTimer(long incrementInterval) {
        this(Integer.MAX_VALUE, incrementInterval);
    }

    /**
     * Cancel the increment.
     */
    public synchronized final void cancel() {
        mCancelled = true;
        mHandler.removeMessages(MSG);
    }

    /**
     * Start the increment.
     */
    public synchronized final IncrementTimer start() {
        mCancelled = false;
        if (mMillisInFuture <= 0) {
            onFinish();
            return this;
        }
        mHandler.sendMessage(mHandler.obtainMessage(MSG));
        return this;
    }


    /**
     * Callback fired on regular interval.
     *
     * @param millisPassed The amount of time passed yet.
     */
    public abstract void onTick(long millisPassed);

    /**
     * Callback fired when the time is up.
     */
    public abstract void onFinish();


    private static final int MSG = 1;


    // handles time increment.
    private Handler mHandler = new Handler(new Handler.Callback() {
        @Override
        public boolean handleMessage(Message msg) {
            synchronized (IncrementTimer.this) {
                if (mCancelled) {
                    return true;
                }

                if (mMillisPassed < mMillisInFuture) {
                    long leftMillis = mMillisInFuture - mMillisPassed;
                    long delay;
                    if (leftMillis > mIncrementInterval) {
                        delay = mIncrementInterval;
                    } else {
                        delay = leftMillis;
                    }
                    mMillisPassed += delay;
                    onTick(mMillisPassed);
                    mHandler.sendMessageDelayed(mHandler.obtainMessage(MSG), delay);
                } else if (mMillisPassed >= mMillisInFuture) {
                    onFinish();
                }

//                final long millisLeft = mStopTimeInFuture - SystemClock.elapsedRealtime();
//
//                if (millisLeft <= 0) {
//                    onFinish();
//                } else if (millisLeft < mIncrementInterval) {
//                    // no tick, just delay until done
//                    mHandler.sendMessageDelayed(mHandler.obtainMessage(MSG), millisLeft);
//                } else {
//                    long lastTickStart = SystemClock.elapsedRealtime();
//                    onTick(millisLeft);
//
//                    // take into account user's onTick taking time to execute
//                    long delay = lastTickStart + mIncrementInterval - SystemClock.elapsedRealtime();
//
//                    // special case: user's onTick took more than interval to
//                    // complete, skip to next interval
//                    while (delay < 0) delay += mIncrementInterval;
//
//                    mHandler.sendMessageDelayed(mHandler.obtainMessage(MSG), delay);
//                }
                return true;
            }
        }
    });

}