D-Net

package eu.dnetlib.data.emailSender;

import org.apache.log4j.Logger;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.context.support.WebApplicationContextUtils;

import javax.servlet.ServletContextEvent;

import javax.servlet.ServletContextListener;

import java.util.Calendar;

import java.util.concurrent.Executors;

import java.util.concurrent.ScheduledExecutorService;

import java.util.concurrent.ScheduledFuture;

import static java.util.concurrent.TimeUnit.SECONDS;

/**

 * Created by kiatrop on 10/5/2017.

 */

public class EmailScheduler implements ServletContextListener {

    private int delay = 0;

    private final Logger logger = Logger.getLogger(EmailScheduler.class);

    private static boolean sendEmailNotifications;

    @Autowired

    private String beautySleep;

    @Autowired

    private String targetHour;

    @Autowired

    private String targetMinute;

    @Autowired

    private String targetSecond;

    @Autowired

    private EmailSender emailSender;

    private final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1);

    @Override

    public void contextInitialized(ServletContextEvent servletContextEvent) {

        WebApplicationContextUtils

                .getRequiredWebApplicationContext(servletContextEvent.getServletContext())

                .getAutowireCapableBeanFactory()

                .autowireBean(this);

        if(sendEmailNotifications) {

            logger.debug("Initializing EmailScheduler with beautySleep " + beautySleep + " and begin time " + targetHour + ":" + targetMinute + ":" + targetSecond + " and email sender " + emailSender);

            delay = getInitialDelaySeconds(Integer.parseInt(targetHour), Integer.parseInt(targetMinute), Integer.parseInt(targetSecond));

            logger.debug("EmailScheduler will wait " + delay + " seconds");

            final ScheduledFuture<?> resetHandle = scheduler.scheduleAtFixedRate(emailSender, delay, Integer.parseInt(beautySleep), SECONDS);

        } else {

            logger.debug("Shutting down EmailScheduler for claim notifications");

            scheduler.shutdown();

        }

    }

    @Override

    public void contextDestroyed(ServletContextEvent servletContextEvent) {

        if(!scheduler.isShutdown()) {

            logger.info("Shutting down EmailScheduler.");

            scheduler.shutdown();

        } else {

            logger.info("EmailScheduler is already shutdown");

        }

    }

    private int getInitialDelaySeconds(int targetHour, int targetMinute, int targetSecond) {

        int delay = 0;  // delay in seconds

        // calculate second of target run time within a day

        int target = targetHour*60*60+targetMinute*60+targetSecond;

        // calculate second of current time within a day

        Calendar calendar = Calendar.getInstance();

        int second = calendar.get(Calendar.SECOND);

        int minute = calendar.get(Calendar.MINUTE);

        int hour = calendar.get(Calendar.HOUR_OF_DAY);

        int current = hour*60*60+minute*60+second;

        if(target > current) {

            delay = target - current;

        } else {

            // one day has 86400 seconds

            delay = 86400 - (current - target);

        }

        return delay;

    }

    public void setEmailSender(EmailSender emailSender) {

        this.emailSender = emailSender;

    }

    public void setSendEmailNotifications(boolean sendEmailNotifications) { this.sendEmailNotifications = sendEmailNotifications; }

    public boolean getSendEmailNotifications() { return sendEmailNotifications; }

    public void setBeautySleep(String beautySleep) {

        this.beautySleep = beautySleep;

    }

    public String getBeautySleep() {

        return beautySleep;

    }

    public EmailSender getEmailSender() {

        return emailSender;

    }

    public String getTargetHour() {

        return targetHour;

    }

    public void setTargetHour(String targetHour) {

        this.targetHour = targetHour;

    }

    public String getTargetMinute() {

        return targetMinute;

    }

    public void setTargetMinute(String targetMinute) {

        this.targetMinute = targetMinute;

    }

    public String getTargetSecond() {

        return targetSecond;

    }

    public void setTargetSecond(String targetSecond) {

        this.targetSecond = targetSecond;

    }

}