IMAP presents mail messages as entries in a hierarchy of folders, one of which will be an inbox.
Java Mail comes with Provider implementations for POP3 and IMAP, and the secure versions of those as POP3S and IMAPS.
This HowTo connects to a Google Mail account with IMAPS. IMAP protocol is more advanced than POP. With IMAP, you can talk back to the server and sync your changes automatically.
This Howto connects to a server using the IMAPS (Secure, encrypted IMAP) to download messages with or without attachments and save them into files.
import java.io.*; import java.util.*; import javax.mail.*; import javax.mail.internet.*; public class ReceiveMailImap { public ReceiveMailImap() {} // // inspired by : // http://www.mikedesjardins.net/content/2008/03/using-javamail-to-read-and-extract/ // public static void doit() throws MessagingException, IOException { Folder folder = null; Store store = null; try { Properties props = System.getProperties(); props.setProperty("mail.store.protocol", "imaps"); Session session = Session.getDefaultInstance(props, null); // session.setDebug(true); store = session.getStore("imaps"); store.connect("imap.gmail.com","myemail@gmail.com", "******"); folder = store.getFolder("Inbox"); /* Others GMail folders : * [Gmail]/All Mail This folder contains all of your Gmail messages. * [Gmail]/Drafts Your drafts. * [Gmail]/Sent Mail Messages you sent to other people. * [Gmail]/Spam Messages marked as spam. * [Gmail]/Starred Starred messages. * [Gmail]/Trash Messages deleted from Gmail. */ folder.open(Folder.READ_WRITE); Message messages[] = folder.getMessages(); System.out.println("No of Messages : " + folder.getMessageCount()); System.out.println("No of Unread Messages : " + folder.getUnreadMessageCount()); for (int i=0; i < messages.length; ++i) { System.out.println("MESSAGE #" + (i + 1) + ":"); Message msg = messages[i]; /* if we don''t want to fetch messages already processed if (!msg.isSet(Flags.Flag.SEEN)) { String from = "unknown"; ... } */ String from = "unknown"; if (msg.getReplyTo().length >= 1) { from = msg.getReplyTo()[0].toString(); } else if (msg.getFrom().length >= 1) { from = msg.getFrom()[0].toString(); } String subject = msg.getSubject(); System.out.println("Saving ... " + subject +" " + from); // you may want to replace the spaces with "_" // the TEMP directory is used to store the files String filename = "c:/temp/" + subject; saveParts(msg.getContent(), filename); msg.setFlag(Flags.Flag.SEEN,true); // to delete the message // msg.setFlag(Flags.Flag.DELETED, true); } } finally { if (folder != null) { folder.close(true); } if (store != null) { store.close(); } } } public static void saveParts(Object content, String filename) throws IOException, MessagingException { OutputStream out = null; InputStream in = null; try { if (content instanceof Multipart) { Multipart multi = ((Multipart)content); int parts = multi.getCount(); for (int j=0; j < parts; ++j) { MimeBodyPart part = (MimeBodyPart)multi.getBodyPart(j); if (part.getContent() instanceof Multipart) { // part-within-a-part, do some recursion... saveParts(part.getContent(), filename); } else { String extension = ""; if (part.isMimeType("text/html")) { extension = "html"; } else { if (part.isMimeType("text/plain")) { extension = "txt"; } else { // Try to get the name of the attachment extension = part.getDataHandler().getName(); } filename = filename + "." + extension; System.out.println("... " + filename); out = new FileOutputStream(new File(filename)); in = part.getInputStream(); int k; while ((k = in.read()) != -1) { out.write(k); } } } } } } finally { if (in != null) { in.close(); } if (out != null) { out.flush(); out.close(); } } } public static void main(String args[]) throws Exception { ReceiveMailImap.doit(); } }
Done! Happy Coding!
Related posts:
Java Program to Construct an Expression Tree for an Prefix Expression
Spring Boot Actuator
Java Program to Check whether Graph is a Bipartite using DFS
Java Program to Find Minimum Element in an Array using Linear Search
Spring Cloud – Adding Angular
Removing Elements from Java Collections
Checking for Empty or Blank Strings in Java
Java Program to Find Hamiltonian Cycle in an UnWeighted Graph
Guide to java.util.concurrent.BlockingQueue
Java Program to Implement Control Table
Working with Tree Model Nodes in Jackson
Spring Boot - Introduction
Debugging Reactive Streams in Java
A Guide to JUnit 5
Java Program to Implement Interval Tree
Java Program to Evaluate an Expression using Stacks
Send email with JavaMail
ThreadPoolTaskExecutor corePoolSize vs. maxPoolSize
Java Program to Implement Min Heap
Spring Webflux and CORS
Custom Exception trong Java
Làm thế nào tạo instance của một class mà không gọi từ khóa new?
Java Program to implement Bit Set
Java Program to Implement ArrayDeque API
A Custom Media Type for a Spring REST API
Java Program to Find kth Smallest Element by the Method of Partitioning the Array
Mệnh đề if-else trong java
Period and Duration in Java
Java Program to Implement Hopcroft Algorithm
Java Program to Implement TreeSet API
ExecutorService – Waiting for Threads to Finish
Using the Not Operator in If Conditions in Java