利用JavaMail通过POP3协议、IMAP协议收取Gmail邮箱

Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
final String SSL_FACTORY = "javax.net.ssl.SSLSocketFactory";
// Get a Properties object
Properties props = System.getProperties();
props.setProperty("mail.pop3.socketFactory.class", SSL_FACTORY);
props.setProperty("mail.pop3.socketFactory.fallback", "false");
props.setProperty("mail.pop3.port", "995");
props.setProperty("mail.pop3.socketFactory.port", "995");
props.setProperty("mail.pop3.disabletop", "true");
props.setProperty("mail.pop3.ssl.enable", "true");
props.setProperty("mail.pop3.useStartTLS", "true");

// 以下步骤跟一般的JavaMail操作相同
Session session = Session.getDefaultInstance(props, null);
URLName urln = new URLName("pop3", "pop.gmail.com", 995, null, username, password);
Store store = session.getStore(urln);
store.connect();

Folder inbox = null;
try {
store.connect();

inbox = store.getFolder("INBOX");
inbox.open(Folder.READ_ONLY);
FetchProfile profile = new FetchProfile();
profile.add(FetchProfile.Item.ENVELOPE);
//			profile.add(FetchProfile.Item.CONTENT_INFO);
//			profile.add(FetchProfile.Item.FLAGS);
profile.add(UIDFolder.FetchProfileItem.UID);
Message[] messages = inbox.getMessages();
inbox.fetch(messages, profile);
System.out.println("收件箱的邮件数：" + messages.length);
for (int i = 0; i < messages.length; i++) {

// 邮件发送者
String from = decodeText(messages[i].getFrom()[0].toString());
InternetAddress ia = new InternetAddress(from);
System.out.println("FROM:" + ia.getPersonal() + '(' + ia.getAddress() + ')');
// 邮件标题
System.out.println("TITLE:" + messages[i].getSubject());
// 邮件大小
System.out.println("SIZE:" + messages[i].getSize());
// 邮件发送时间
System.out.println("DATE:" + messages[i].getSentDate());
//邮件ID
String uid = ((POP3Folder)inbox).getUID(messages[i]);
System.out.println("UID:"+ uid);
//收件人
String to = decodeText(messages[i].getAllRecipients()[0].toString());
InternetAddress iaTo = new InternetAddress(to);
System.out.println("TO:" + iaTo.getPersonal() + '(' + iaTo.getAddress() + ')');
//内容
//				String disposition;
//				Multipart mp = (Multipart) messages[i].getContent();
//				int mpCount = mp.getCount();
//				System.out.println("");
//				for (int m = 0; m < mpCount; m++){
//
//					BodyPart part = mp.getBodyPart(m);
//					disposition = part.getDisposition();
//					if (disposition != null && disposition.equals(Part.ATTACHMENT)){
//						//saveAttach(part,Constant.ZIP_DIR);
//					} else{
//						//System.out.println(part.getContent());
//					}
//				}
File f = new File("/mail/test"+uid+".eml");
messages[i].writeTo(new FileOutputStream(f));
}
} finally {
try {
inbox.close(false);
} catch (Exception e) {
}
try {
store.close();
} catch (Exception e) {
}

}