Android 使用DelayQueue实现串口三次重发数据

串口通信要求没收到返回重新发送，最多三次。三次过后提示无响应。早前试过用postdelay，然后收到数据后用removeall，这样其实所有的都被清除了，不是对应的命令。而且代码非常不美观，runnable很多。（问题其实也很多）

后来发送的使用延时队列

  public void send(byte[] data,int DP) {
        for(int i = 0;i<4;i++){
            DelayFrame one = new DelayFrame(DP,data,i);
            delayQueue.offer(one);
        }
    }

    class DelayRunnable implements Runnable {
        @Override
        public void run() {
            while (isRunnable) {
                try {
                    DelayFrame frame = delayQueue.take();
                    if (frame.getTimes() == 3) {
                        EventBus.getDefault().post(new FrameBean(999));
                        continue;
                    }
                    if (mOutputStream != null) {
                        mOutputStream.write(frame.getData());
                        mOutputStream.flush();
                    }
                } catch (Exception e) {
                    System.out.println("233333333:"+e.getMessage());
                    throw new RuntimeException(e);
                }
            }
        }
    }

take()是阻塞的，会等到下一个到期的事件，每次发送的时候添加4个事件。具体DelayFrame代码

public class DelayFrame implements Delayed {
    private final long endTime;
    private final int DP;
    private final int times;
    private final byte[] data;


    public DelayFrame(int DP, byte[] data,int times) {
        this.DP = DP;
        this.data = data;
        this.times = times;
        int delayTime = 1000;
        this.endTime = System.currentTimeMillis() + (long) delayTime *times;
    }


    public int getDP() {
        return DP;
    }

    public byte[] getData() {
        return data;
    }

    public int getTimes() {
        return times;
    }

    @Override
    public long getDelay(TimeUnit unit) {
        long remainingDelay = endTime - System.currentTimeMillis();
        if (remainingDelay <= 0) {
            return 0;
        }
        return unit.convert(remainingDelay, TimeUnit.MILLISECONDS);
    }

    @Override
    public int compareTo(Delayed o) {
        return Long.compare(this.endTime, ((DelayFrame) o).endTime);
    }
}

最后收到数据后删除对应还没到期的

    private void removeDelay(int dp){
        Iterator<DelayFrame> iterator = delayQueue.iterator();
        while (iterator.hasNext()) {
            DelayFrame frame = iterator.next();
             if(frame.getDP() == dp) {
                 iterator.remove();
             }
        }
    }