Question

I have a servlet that pulls data from a text file during initialization. Now I am updating that text file with a cron job(say everyday at 10am) and want to reinitialize the servlet every time this particular file changes.

Second approach I can follow is to sync the reinitialization of the servlet to my cron job.

请就如何实施上述两种办法提出建议。

thanks.

Answer 1

Don被搁置,成为珍视物的典型变量。创建rel=“noreferer”>SppleedExcutorservice/code>。



E.g.

@WebListener
public class Config implements ServletContextListener {

    private ScheduledExecutorService scheduler;

    @Override
    public void contextInitialized(ServletContextEvent event) {
        Data data = new Data(); // Your class which reads and holds data upon construction.
        event.getServletContext().setAttribute("data", data);
        scheduler = Executors.newSingleThreadScheduledExecutor();
        scheduler.scheduleAtFixedRate(new Reloader(data), 0, 1, TimeUnit.DAYS);
    }

    @Override
    public void contextDestroyed(ServletContextEvent event) {
        scheduler.shutdownNow();
    }

}


页: 1

public class Reloader implements Runnable {

    private Data data;

    public Reloader(Data data) {
        this.data = data;
    }

    @Override
    public void run() {
        data.reload();
    }

}


它可以随意取用。

@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) {
    Data data = (Data) getServletContext().getAttribute("data");
    // ...
}


即便是随机联合调查组。

${data.something}

Answer 2

您的服务器偶尔会与一位时间者核对文件,以便进行改动。

“贾瓦变化监测档案”将介绍许多例子,其中之一可在此查阅:。

友情链接