Hi Milind, a cron job is a program that starts at a predefined date and time. An MDB is a bean that is called when a message (portion of data) comes in.
It depends what you want to do. You cannot do some particular things from the bean code which runs inside the EJB container. For example, it is forbidden to use the java.io package or do multithreading tricks. If your app requires these, it may indeed make sense to schedule a cron job that runs a stand-alone Java client which calls the beans in the app server remotely, gets data from there and writes it to files or whatever it needs to do. HTH, Matthias ---- Matthias Bohlen Consulting that helps project teams to succeed... Web: http://www.mbohlen.de/ Snail: Luise-Albertz-Str. 25 D-53340 Meckenheim Germany Phone: +49 (170) 772 8545 Fax: +49 (2225) / 945189 > -----Original Message----- > From: A mailing list for Enterprise JavaBeans development > [mailto:[EMAIL PROTECTED]]On Behalf Of Nitin Goyal > Sent: Friday, December 20, 2002 9:25 AM > To: [EMAIL PROTECTED] > Subject: Re: Message Driven Bean > > > Hi, > > If it helps to put things in perspective, MDB is the J2EE > implementation > of MOM (Message oriented Middleware). In messaging systems, 2 or more > applications exchange information in forms of messages asynchronously. > In this scenario, a message is a self contained unit of data and/or > routhing headers. > > In your case (as I understand) Unix crons are running asynchronously, > but there are no interchange of messaging between > applications that fire > or use the crons. They simply just get alive at a particular specified > time and complete their designated tasks. > > Additions/Corrections Welcome. > Thanks, > Nitin > > Milind Kulkarni wrote: > > >Hi All, > > > >We are developing a several batch programs. The batch > programs are invoked > >using Unix CRON job at a specified time. Somebody told us > that it would be > >better if we can use MDB. > > > >I have the following questions in this regard: > > > >1. Will we still need Unix CRONs to invoke batch program if > we decide to > >use MDBs? If no, how we can schedule batches using MDB? > >2. What are the real advantages of using MDB over CRON? > > > > > >Thanks & Regards, > >Milind > > > >============================================================= > ============== > >To unsubscribe, send email to [EMAIL PROTECTED] and > include in the body > >of the message "signoff EJB-INTEREST". For general help, > send email to > >[EMAIL PROTECTED] and include in the body of the message "help". > > > > > > > > > > ============================================================== > ============= > To unsubscribe, send email to [EMAIL PROTECTED] and > include in the body > of the message "signoff EJB-INTEREST". For general help, > send email to > [EMAIL PROTECTED] and include in the body of the message "help". > > =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff EJB-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
