如何在这个嵌入式程序中不使用全局变量？

Question

我相信我们公司有一个边缘案例，它阻止我进入“从不使用全局变量阵营”。

我们需要编写一个在我们的盒子中运行的嵌入式应用程序，它可以从医院的设备中提取医疗数据。

即使医疗设备被切断、网络中断或我们的盒子设置发生变化，它也应该无限运行。设置是从 .txt 文件中读取的，可以在运行时更改，最好没有问题。

这就是为什么单例模式对我没用。所以我们不时返回（读取 1000 条数据后）并读取设置，如下所示：

public static SettingForIncubator settings;

public static void main(String[] args) {
    while(true){
        settings = getSettings(args);

        int counter=0;

        while(medicalDeviceIsGivingData && counter < 1000){
            byte[] data = readData(); //using settings

            //a lot of of other functions that use settings.

            counter++;
        }
        Thread.Sleep(100); //against overheating and CPU usage.
    } 
    public byte[] readData(){
    //read Data from the port described in settings variable
    }
}

还有其他方法可以设计程序吗？

Answer 1

我不知道你的意思，但我认为这段代码会对你有所帮助：

class SettingsForIncubator {
}

public class MedicalProcessor {

    protected volatile boolean active;
    protected volatile boolean medicalDeviceIsGivingData;

    public void start(String[] args) throws Exception {
        this.active = true;
        Thread thread = new Thread(() -> loop(args));
        thread.start();
    }

    protected void loop(String[] args) {
        System.out.println("start");
        while(active) {
            SettingsForIncubator settings = getSettings(args);
            int counter=0;

            while(medicalDeviceIsGivingData && counter < 1000){
                byte[] data = readData(settings); //using settings

                //a lot of of other functions that use settings.

                counter++;
            }
            try {
                Thread.sleep(100); //against overheating and CPU usage.
            }
            catch (Exception e) {
                break;
            }
        }
    }

    protected byte[] readData(SettingsForIncubator settings) {
        // logic read data
        return null;
    }

    protected SettingsForIncubator getSettings(String[] args) {
        // logic to get settings
        return null;
    }

    public void stop() {
        this.active = false;
    }

    public static void main(String[] args) throws Exception {
        MedicalProcessor processor = new MedicalProcessor();
        processor.start(args);
    }

}