How to refer to a particular message

Question

Hi all,
In java mail api's it is mentioned
Since message numbers can change within a session if the folder is expunged , clients are advised not to use message numbers as references to messages. Use Message objects instead.
but while developing web based email system ( like yahoo).....
i first collect 10 msgs from folder and display them .
now to give some reference to these 10 msgs i need to give some identification so that when user selects one of these message it would lead to different screen which will display the content of that message.
And this identification is message No. In the other screen i get this message no use this method
folder.getMessage( msgno);
Giving message number identification is unsafe only when user do some delete action on that folder. In my programme after deleting the message the folder is expunged closed and re-opened and then again 10 msgs are displayed on screen.
I guess it wont be a problem.
In API's it is said that instead of message number message objects can be used for reference. But i cant find any method in folder class where i can get a message with any other reference than message number.
does anyone have a better solution to this.

Answer 1

When you perform a Folder.getMessages() you get an array of Messages returned. This is your list of objects that reference messages. The api doc states that this reference always refers to a message regardless of whether the message number changes due to an expunge. So this insulates you from the volatility associated with message numbers.
The issue you have to deal with is whether a change took place to inbox in between the time you performed the Folder.getMessages()] and the next action upon the mailbox. Specifically, you should code to handle the expunging of the message outside of your application, by testing isExpunged and catching MessageRemovedExceptions. With every interaction you should refresh the message list, ingoring messages marked as expunged.
I hope that helps.