JavaMail API for Unread yahoo messages not working.

Folder folder = store.getFolder("inbox");
folder.open(Folder.READ_WRITE);
Messages[] messages = folder.search(new FlagTerm(new Flags(Flags.Flag.SEEN), false));

using this logic i am able to get all unread messages in my gmail account, but the same logic i tried with yahoo account. it is giving all mails in my inbox.
how to get unread mails in yahoo using javamail API???

Thanks.

Gmail is IMAP, whereas Yahoo Mail is POP, if memory serves. From http://java.sun.com/developer/onlineTraining/JavaMail/contents.html#JavaMailDeleting:

Just because a flag exists doesn't mean the flag is supported by all mail servers/providers. For instance, besides deleting messages, the POP protocol supports none of them. Checking for new mail is not a POP task but one built into mail clients. To find out what flags are supported, ask the folder with getPermanentFlags().

ok...i read this link.
new mail messages they have, are not supported by POP at all.
but my question is how to get new mail with different logic.???

Since POP doesn't support this, you need to code it in your client. Store all message IDs of mails you've already seen, and when you connect the next time, filter out all messages with those IDs.

great idea...ok i will do this...thanks for nice information.

Thank you very very much.