cleandaylimitordersbean.java

ejb开发源码

package examples;

import javax.ejb.*;
import java.util.Calendar;
import java.util.TimeZone;
import java.util.SimpleTimeZone;
import java.util.GregorianCalendar;
import java.util.Date;

public class CleanDayLimitOrdersBean implements SessionBean, TimedObject {

     private SessionContext context;
     
     public void cleanPeriodicallyDayLimitOrders() {
	    // Get hold of the eastern time zone assuming that the securities are being 
          // traded on NYSE and NASDAQ exchanges.
          String[] timezoneIDs = TimeZone.getAvailableIDs (-5 * 60 * 60 * 1000);

	    SimpleTimeZone est = new SimpleTimeZone (-5 * 60 * 60 * 1000, timezoneIDs[0]);

          // Provide the rules for start and end days of daylight savings time.
	    est.setStartRule (Calendar.APRIL, 1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);
	    est.setEndRule (Calendar.OCTOBER, -1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);

          // Get hold of a calendar instance for the eastern time zone.
	    Calendar cal = new GregorianCalendar(est);

          // Set the calendar to the current time.
	    cal.setTime (new Date ());
	
          // Calculate the difference between now and market close i.e. 4 PM Eastern.
	    int hourofday = cal.get (cal.HOUR_OF_DAY);
	    int minuteofhour = cal.get (cal.MINUTE);

          // If this method is invoked after the market close, then set the timer expiration
          // immediately i.e. start=0. Otherwise, calculate the milliseconds that needs
          // to elapse until first timer expiration.
	    long start = 0;
	    if (hourofday < 16)
	    {
	         int hourdiff = 16 - hourofday - 1;
		   int mindiff = 60 - minuteofhour;
			
		   start = (hourdiff * 60 * 60 * 1000) + (mindiff * 60 * 1000);
	    }

          // Finally, get hold of the timer service instance from EJBContext object and create the 
          // recurrent expiration timer.
          TimerService timerService = context.getTimerService();
          Timer timer = timerService.createTimer(start, 86400000, null);

          System.out.println("CleanDayLimitOrdersBean: Timer created to first expire after " + start + " milliseconds.");
     }

     public void ejbTimeout(Timer timer) {
  
          System.out.println("CleanDayLimitOrdersBean: ejbTimeout called.");

          // Put here the code for cleaning the database of day limit orders that have
          // not been executed.
     }

     public void setSessionContext(SessionContext sc) {
          System.out.println("CleanDayLimitOrdersBean: setSessionContext called.");
          context = sc;
     }

     public void ejbCreate() {
          System.out.println("CleanDayLimitOrdersBean: ejbCreate called.");
     }

     public CleanDayLimitOrdersBean() {}
     public void ejbRemove() {}
     public void ejbActivate() {}
     public void ejbPassivate() {}
}