@Override
    public synchronized boolean cancel(boolean mayInterruptIfRunning) {
        if (isCancelled) {
            return true;
        }

        final boolean result = !isDone();
        if (result) {
            isCancelled = true;
            if (mayInterruptIfRunning) {
                clear();
            }
            waiter.notifyAll(this);
        }
        return result;
    }
Constructor for a RequestFutureTarget. Should not be used directly.
core/src/main/java/com/bumptech/glide/request/RequestFutureTarget.java