Cómo leer correos de GMail desde Java

import java.io.InputStream;

import java.util.Properties;

import javax.mail.Address;

import javax.mail.BodyPart;

import javax.mail.Flags;

import javax.mail.Folder;

import javax.mail.Message;

import javax.mail.MessagingException;

import javax.mail.Multipart;

import javax.mail.NoSuchProviderException;

import javax.mail.Part;

import javax.mail.Session;

import javax.mail.Store;

import javax.mail.internet.MimeMultipart;

import javax.mail.search.FlagTerm;

@SuppressWarnings("all")

public class InboxReader {

public static void main(String args[]) {

Properties props = System.getProperties();

// Uncomment if you are using proxy server to access Internet

/* props.setProperty("http.proxyHost", "192.168.0.1");

props.setProperty("http.proxyPort", "8080"); */

props.setProperty("mail.store.protocol", "imaps");

try {

Session session = Session.getDefaultInstance(props, null);

session.setDebug(true);

Store store = session.getStore("imaps");

store.connect("imap.gmail.com", "email@gmail.com", "PASSWORD");

System.out.println(store);

Folder inbox = store.getFolder("Inbox");

inbox.open(Folder.READ_ONLY);

FlagTerm ft = new FlagTerm(new Flags(Flags.Flag.SEEN), false);

Message messages[] = inbox.search(ft);

for (Message message : messages) {

// message.setFlag(Flags.Flag.ANSWERED, true);

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

String subject = message.getSubject();

String content = message.getContentType();

MimeMultipart part = (MimeMultipart) message.getContent();

BodyPart bodyPart = part.getBodyPart(0);

part.getContentType();

part.getCount();

part.getPreamble();

try {

printParts(message);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

Flags flags = message.getFlags();

Address[] form = message.getFrom();

}

} catch (NoSuchProviderException e) {

e.printStackTrace();

System.exit(1);

} catch (MessagingException e) {

e.printStackTrace();

System.exit(2);

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static void printParts(Part p) throws Exception {

Object o = p.getContent();

if (o instanceof String) {

System.out.println("This is a String");

System.out.println((String) o);

} else if (o instanceof Multipart) {

System.out.println("This is a Multipart");

Multipart mp = (Multipart) o;

int count = mp.getCount();

for (int i = 0; i < count; i++) {

printParts(mp.getBodyPart(i));

}

} else if (o instanceof InputStream) {

System.out.println("This is just an input stream");

InputStream is = (InputStream) o;

int c;

// while ((c = is.read()) != -1)

// System.out.write(c);

}

}

}