I’ve probably used Java to send email somewhere in the neighborhood of 30 times and have never really had much trouble with it. But how in blazes do I connect to a (Pop3) account and pull down email? Well, after much cursing at the javamail API the solution crystallized to something containing the following:

Properties props = new Properties();
Session session = Session.getDefaultInstance(props, null);
store = session.getStore("pop3");
store.connect( "mail.isp.com", "myUserName", "myPassword" );
inbox = store.getFolder("INBOX");
inbox.open(Folder.READ_ONLY);
Message[] msgs = inbox.getMessages();
// Do something with the messages here
inbox.close(false);
store.close();


It should be noted that the elusive activation.jar and mail.jar from J2EE 1.4 were used to get the above to compile and run. When I tried using the JEE5 libraries, I didn’t have a POP3 implementation and got “JavaMail – NoSuchProviderException: No provider for pop3″ exceptions.

Here’s a code snippet that will show you all of the providers you have available to you:


Properties props = new Properties();
Session session = Session.getDefaultInstance(props, null);
Provider[] p = session.getProviders();
for (int i=0;i System.out.println(p[i].getProtocol());
}


I get back the results: imap, pop3, smtp.