new Thread(() -> { BNRoutePlanInfos routePlaneInfo = BaiduNaviManagerFactory.getRoutePlanManager().getRoutePlanInfo(); if (routePlaneInfo != null) { // 获取限行数据 limitInfo = routePlaneInfo.getLimitInfo(); //3Tab数据 mRoutePlanItems = routePlaneInfo.getRouteTabInfos(); //路线详情 mRouteDetails = routePlaneInfo.getRouteDetailLists(); } }).start(); if (limitInfo != null) { for (int i = 0; i < limitInfo.size(); i++) { String[] arr = limitInfo.get(i).split(","); Log.e(TAG, "第" + arr[0] + "条路线限行消息：" + arr[1]); } } 以上代码有什么问题?帮我改一下

以上代码存在线程安全问题，因为子线程可能还没有执行完毕，主线程就已经进入 if 判断，导致 limitInfo 为 null，从而抛出 NullPointerException 异常。可以使用 CountDownLatch 或者 Handler 来解决线程安全问题，例如：

CountDownLatch latch = new CountDownLatch(1);

new Thread(() -> {
    BNRoutePlanInfos routePlaneInfo = BaiduNaviManagerFactory.getRoutePlanManager().getRoutePlanInfo();
    if (routePlaneInfo != null) {
        // 获取限行数据
        limitInfo = routePlaneInfo.getLimitInfo();
        //3Tab数据
        mRoutePlanItems = routePlaneInfo.getRouteTabInfos();
        //路线详情
        mRouteDetails = routePlaneInfo.getRouteDetailLists();
    }
    latch.countDown();
}).start();

try {
    latch.await();
} catch (InterruptedException e) {
    e.printStackTrace();
}

if (limitInfo != null) {
    for (int i = 0; i < limitInfo.size(); i++) {
        String[] arr = limitInfo.get(i).split(",");
        Log.e(TAG, "第" + arr[0] + "条路线限行消息：" + arr[1]);
    }
}

或者：

Handler handler = new Handler(Looper.getMainLooper()) {
    @Override
    public void handleMessage(@NonNull Message msg) {
        if (msg.what == 1) {
            if (limitInfo != null) {
                for (int i = 0; i < limitInfo.size(); i++) {
                    String[] arr = limitInfo.get(i).split(",");
                    Log.e(TAG, "第" + arr[0] + "条路线限行消息：" + arr[1]);
                }
            }
        }
    }
};

new Thread(() -> {
    BNRoutePlanInfos routePlaneInfo = BaiduNaviManagerFactory.getRoutePlanManager().getRoutePlanInfo();
    if (routePlaneInfo != null) {
        // 获取限行数据
        limitInfo = routePlaneInfo.getLimitInfo();
        //3Tab数据
        mRoutePlanItems = routePlaneInfo.getRouteTabInfos();
        //路线详情
        mRouteDetails = routePlaneInfo.getRouteDetailLists();
    }
    handler.sendEmptyMessage(1);
}).start();