JavaMail reading recent unread mails using IMAP

Question

I have a requirement to retrieve unread mails from Gmail. I am using Java Mail API. By default, this API retrieves mails from the oldest to newest. But I need to retrieve recent mails first. Is it possible? Thanks in advance.

Answer 1

Here is example. Do not forget to add javax.mail in your classpath.

import javax.mail.*; import javax.mail.search.FlagTerm; import java.util.*;  public class GmailFetch {    public static void main( String[] args ) throws Exception {      Session session = Session.getDefaultInstance(new Properties( ));     Store store = session.getStore("imaps");     store.connect("imap.googlemail.com", 993, "[email protected]", "password");     Folder inbox = store.getFolder( "INBOX" );     inbox.open( Folder.READ_ONLY );      // Fetch unseen messages from inbox folder     Message[] messages = inbox.search(         new FlagTerm(new Flags(Flags.Flag.SEEN), false));      // Sort messages from recent to oldest     Arrays.sort( messages, ( m1, m2 ) -> {       try {         return m2.getSentDate().compareTo( m1.getSentDate() );       } catch ( MessagingException e ) {         throw new RuntimeException( e );       }     } );      for ( Message message : messages ) {       System.out.println(            "sendDate: " + message.getSentDate()           + " subject:" + message.getSubject() );     }   } } 

Answer 2

Make sure to use the IMAP protocol, as it supports for flagging.

Do following changes to your code:

1. replace inbox.open( Folder.READ_ONLY ); by inbox.open( Folder.READ_WRITE );

2. Then after reading the message, set the flag like so:

   message.setFlag(Flags.Flag.SEEN, true); 

Full example:

    import javax.mail.*;     import javax.mail.search.FlagTerm;     import java.util.*;      public class GmailFetch {        public static void main( String[] args ) throws Exception {          Session session = Session.getDefaultInstance(new Properties( ));         Store store = session.getStore("imaps");         store.connect("imap.googlemail.com", 993, "[email protected]", "password");         Folder inbox = store.getFolder( "INBOX" );         inbox.open( Folder.READ_WRITE );          // Fetch unseen messages from inbox folder         Message[] messages = inbox.search(             new FlagTerm(new Flags(Flags.Flag.SEEN), false));          // Sort messages from recent to oldest         Arrays.sort( messages, ( m1, m2 ) -> {           try {             return m2.getSentDate().compareTo( m1.getSentDate() );           } catch ( MessagingException e ) {             throw new RuntimeException( e );           }         } );          for ( Message message : messages ) {           System.out.println(                "sendDate: " + message.getSentDate()               + " subject:" + message.getSubject() );               message.setFlag(Flags.Flag.SEEN, true);         }       }     }