for (var node : this){ if (node.getState().equals(state)){ return node; }

This code is using a for-each loop to iterate over a collection of nodes (presumably in a tree or graph data structure) represented by the keyword "this". For each node in the collection, it checks if the node's state (presumably represented by a String or enum) is equal to the given "state" parameter. If a node is found with a matching state, it is returned from the method.

Note: this code is written in Java.

相关问题

private void updateShowSeconds() { if (mShowSeconds) { // Wait until we have a display to start trying to show seconds. if (mSecondsHandler == null && getDisplay() != null) { mSecondsHandler = new Handler(); if (getDisplay().getState() == Display.STATE_ON) { mSecondsHandler.postAtTime(mSecondTick, SystemClock.uptimeMillis() / 1000 * 1000 + 1000); } IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF); filter.addAction(Intent.ACTION_SCREEN_ON); mContext.registerReceiver(mScreenReceiver, filter); } } else { if (mSecondsHandler != null) { mContext.unregisterReceiver(mScreenReceiver); mSecondsHandler.removeCallbacks(mSecondTick); mSecondsHandler = null; updateClock(); } } } private final BroadcastReceiver mScreenReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { String action = intent.getAction(); if (Intent.ACTION_SCREEN_OFF.equals(action)) { if (mSecondsHandler != null) { mSecondsHandler.removeCallbacks(mSecondTick); } } else if (Intent.ACTION_SCREEN_ON.equals(action)) { if (mSecondsHandler != null) { mSecondsHandler.postAtTime(mSecondTick, SystemClock.uptimeMillis() / 1000 * 1000 + 1000); } } } }; private final Runnable mSecondTick = new Runnable() { @Override public void run() { if (mCalendar != null) { updateClock(); } mSecondsHandler.postAtTime(this, SystemClock.uptimeMillis() / 1000 * 1000 + 1000); } }; } 编译报错，lframeworks/base/packages/SystemUI/src/com/android/systemui/statusbar/policy/clock.java:115: cannot findlsymbolsymbol method getstate()location: class android.view.Display if (getDisplay().getstate() == Display.STATE_ON) fframeworks/base/packages/SystemUI/src/com/android/systemui/statusbar/policy/clock.java:115: cannot findlsymbolsymbol : variable STATE_ONlocation: class android.view.Display if (getDisplay().getstate() == Display.STATE_ON) fNote: Some input files use or override a deprecated API.Note: Recompile with -xlint:deprecation for details.Note: Some input files use unchecked or unsafe operations.Note: Recompile with -xlint:unchecked for details.2 errorsmake: *** fout/target/common/obi/Apps/SvstemlT intermediates/classes-full-dehun iarl Frror 4l

根据报错信息，可能是因为没有找到 `getstate()` 方法和 `STATE_ON` 变量，这可能是因为你的代码中没有正确引入 `android.view.Display` 类。你可以尝试在代码开头添加以下引入语句：`import android.view.Display;`。另外，你的代码中也存在一些过时的 API 和未检查或不安全的操作，建议使用 `-xlint:deprecation` 和 `-xlint:unchecked` 对代码进行重新编译，以获取更详细的错误信息。

void AGVScheduler::assign_task_to_agv(std::vector<Task>& tasks, std::vector<AGV>& agvs) { // 首先按照任务的完成状态、优先级进行排序 std::sort(tasks.begin(), tasks.end(), [](const Task& task_1, const Task& task_2) { if (task_1.completed != task_2.completed) { return !task_1.completed; } else { return task_1.priority < task_2.priority; } }); for (const auto& task : tasks) { std::cout << "Task name: " << task.id << ", Completed: " << task.completed << ", Priority: " << task.priority << std::endl; } // 遍历任务列表，分配任务给可用的小车 for (auto& task : tasks) { if (!task.completed) { AGV* closest_agv = nullptr; // 初始化为 nullptr while (closest_agv == nullptr) { // 查找可用的小车 for (auto& agv : agvs) { if (agv.getState()) { closest_agv = &agv; break; } } if (closest_agv == nullptr) { // 没有可用的小车，等待一段时间再查找 std::this_thread::sleep_for(std::chrono::seconds(1)); } } // 找到最近的可用小车 int min_distance = INT_MAX; for (auto& agv : agvs) { if (agv.getState()) { int distance = abs(agv.getCurrentX()- task.start_x) + abs(agv.getCurrentY() - task.start_y); if (distance < min_distance) { min_distance = distance; closest_agv = &agv; } } } // 将任务分配给 AGV 对象的起点和终点坐标 closest_agv->setStartCoord(task.start_x, task.start_y); closest_agv->setEndCoord(task.end_x, task.end_y); closest_agv->setState(false); task.completed = true; std::cout << closest_agv->getid() << "," << task.id << endl; } } }，一運行，就卡死，怎麽解決

这个问题可能是由于死锁引起的，因为在任务分配循环中，每个任务可能会等待一个可用的AGV，而AGV也可能在等待任务的分配。为了解决这个问题，可以尝试使用互斥锁来确保任务分配和AGV状态的同步，并且在等待可用AGV时使用条件变量来避免死锁。

以下是修改后的代码示例：

void AGVScheduler::assign_task_to_agv(std::vector<Task>& tasks, std::vector<AGV>& agvs) {
    std::mutex mtx;
    std::condition_variable cv;

    // 首先按照任务的完成状态、优先级进行排序
    std::sort(tasks.begin(), tasks.end(), [](const Task& task_1, const Task& task_2) {
        if (task_1.completed != task_2.completed) {
            return !task_1.completed;
        } else {
            return task_1.priority < task_2.priority;
        }
    });

    for (const auto& task : tasks) {
        std::cout << "Task name: " << task.id << ", Completed: " << task.completed << ", Priority: " << task.priority << std::endl;
    }

    // 遍历任务列表，分配任务给可用的小车
    for (auto& task : tasks) {
        if (!task.completed) {
            AGV* closest_agv = nullptr;

            {
                std::unique_lock<std::mutex> lock(mtx);
                cv.wait(lock, [&]() {
                    for (auto& agv : agvs) {
                        if (agv.getState()) {
                            closest_agv = &agv;
                            return true;
                        }
                    }
                    return false;
                });
            }

            // 找到最近的可用小车
            int min_distance = INT_MAX;
            for (auto& agv : agvs) {
                if (agv.getState()) {
                    int distance = abs(agv.getCurrentX()- task.start_x) + abs(agv.getCurrentY() - task.start_y);
                    if (distance < min_distance) {
                        min_distance = distance;
                        closest_agv = &agv;
                    }
                }
            }

            // 将任务分配给 AGV 对象的起点和终点坐标
            closest_agv->setStartCoord(task.start_x, task.start_y);
            closest_agv->setEndCoord(task.end_x, task.end_y);
            closest_agv->setState(false);
            task.completed = true;

            std::cout << closest_agv->getid() << "," << task.id << endl;

            cv.notify_all();
        }
    }
}

在以上代码中，我们使用了互斥锁和条件变量来确保任务分配和AGV状态的同步。在等待可用AGV时，我们使用了条件变量来避免死锁。当没有可用的AGV时，任务会等待条件变量通知，而在AGV状态改变时，我们使用 `notify_all()` 来通知等待的任务。