往websocket发送消息，先发送暂停后发送一个新的开始命令， 当taskAction为2时是暂停 为 1是开始根据一下代码 补充代码 public void handle(String msg){ try { String[] ms = msg.split(","); if (ms.length == 3 && ms[0].startsWith("$W") && ms[2].startsWith("$C")) { DemoWebSocketClient client = new DemoWebSocketClient(new URI(url)); client.connect(); String nowChannel = ms[2].substring(2, 4); String o = redisTemplate.opsForValue().get("channel:freq:" + nowChannel); if(o != null && o != " "){ if (channel == null) { //TODO 往websocket发送消息，消息发送成功后将channel赋值 client.send(transferDtoToJson(1, Double.parseDouble(o))); channel = nowChannel; } else if (!nowChannel.equals(channel)) { //TODO 往websocket发送消息，先发送暂停后发送一个新的开始命令，消息发送成功后将channel赋值 channel = nowChannel; } } String[] jd = ms[0].substring(2).split("\\*"); double angle = Integer.parseInt(jd[0]) / 100.00D; String[] result = LonLatUtil.calLocationByDistanceAndLocationAndDirection(angle, lon, lat, radius); String value = lon + "," + lat + ";" + result[0] + "," + result[1]; redisTemplate.convertAndSend("vhfDf", value); redisTemplate.opsForValue().set("now:vhf:info", value, 1L, TimeUnit.SECONDS); } } catch (Exception e) { e.printStackTrace(); } }

补充代码如下：

else if (ms.length == 3 && ms[0].startsWith("$W") && ms[2].startsWith("$C")) {
    DemoWebSocketClient client = new DemoWebSocketClient(new URI(url));
    client.connect();
    String nowChannel = ms[2].substring(2, 4);
    String o = redisTemplate.opsForValue().get("channel:freq:" + nowChannel);
    if(o != null && o != " "){
        if (channel == null) {
            //往websocket发送消息，消息发送成功后将channel赋值
            String startMsg = transferDtoToJson(1, Double.parseDouble(o));
            client.send(startMsg);
            channel = nowChannel;
        } else if (!nowChannel.equals(channel)) {
            //往websocket发送消息，先发送暂停后发送一个新的开始命令，消息发送成功后将channel赋值
            String pauseMsg = transferDtoToJson(2, 0);
            client.send(pauseMsg);
            String startMsg = transferDtoToJson(1, Double.parseDouble(o));
            client.send(startMsg);
            channel = nowChannel;
        }
    }
    String[] jd = ms[0].substring(2).split("\\*");
    double angle = Integer.parseInt(jd[0]) / 100.00D;
    String[] result = LonLatUtil.calLocationByDistanceAndLocationAndDirection(angle, lon, lat, radius);
    String value = lon + "," + lat + ";" + result[0] + "," + result[1];
    redisTemplate.convertAndSend("vhfDf", value);
    redisTemplate.opsForValue().set("now:vhf:info", value, 1L, TimeUnit.SECONDS);
}

在第一个if分支中，如果`channel`为空，则需要发送开始命令，待命令发送成功后再将`channel`赋值为当前频道`nowChannel`。如果`channel`不为空且与当前频道不同，则需要先发送暂停命令，待命令发送成功后再发送开始命令，并将`channel`赋值为当前频道`nowChannel`。具体的，暂停命令和开始命令的参数分别为2和1，频道的频率需要根据实际情况进行获取。